It has been shown that Drosophila melanogaster fly to the source of an attractive scent by making a series of highly stereotyped responses to olfactory and visual stimuli (Kellogg, Frizel, and Wright, 1962). The comparable processes by which Aedes aegypti are guided to a warm-blooded host have now been studied and are the subject of this paper.

In a previous communication (Kellogg and Wright, 1962a), we have drawn attention to the role of warm wet convection currents in bringing about the alightment of Aedes aegypti after they have been stimulated to fly by human breath. In some of those experiments, copper bars were warmed at one end and cooled at the other and covered with dampened cloth, and the number of mosquitoes touching or alighting at various points along their length was counted. The results showed that the warm wet end was highly attractive.

The role of warm wet air currents in guiding Aedes aegypti to a host has been described (Kellogg and Wright, 1962a), and it has been shown that a repellent vapor interferes with this guidance (Kellogg and Wright, 1962b). The purpose of this paper is to apply accepted physical principles to the problems which an insect must solve if it is to derive useful information from warm wet convection currents, and to look for ways that a repellent vapor might interfere with the process. This is justifiable even though the conclusions may not correspond in all respects to the mechanisms actually used by the insect, as long as it shows what is in fact physically possible and suggests fruitful lines of enquiry.

During my recent studies on the lepidopterous miners in the needles of various conifers, I have found several undescribed species. One of them occurs near Ottawa, Ontario, and in Nova Scotia. It was also found in Quebec by Dr. J. M. McLeod and Mr. J. A. R. Ducharme, Forest Research Laboratory, Sillery, Quebec. I describe this species here, to enable those officers to report on the immature stages and life history in a companion paper that follows.

Some of my emigrated Dutch friends have with considerable success collected aphids for me in Canada. The following notes are based on some of their catches.

Maculolachnus sijpkensi, new species

Oviparous female.

Body about 3.00-3.60 mm long, rather broadly oval. Head and pronotum brown sclerotic; mesonotum marginally sclerotic, spino-pleurally with small brown scleroites at the bases of the very numerous hairs; such scleroites also present on metanotum and marginally on abd. segment I, and in number at the bases of the hairs of VIIth, rarely also VIth abd. tergite; VIIIth terpite with a sclerotic band, which is narrower and often broken in the middle. No scleroites present at the bases of the spinopleural hairs of abd. tergites I-V or I-VI. Intersegmental sclerites on abdomen small, dark brown to Black. Dorsal hairs very numerous, on IIIrd abd. tergite up to about 0.11 mm long. Antennae darker-brown than the head, about 519 length of body; for interrelation of segments vide measurements; IIIrd segment with 4-11 rhinaria; the tw to seven of them that stand in a row large, elevated and bulging, but if many rhinaria are present often some small ones in the row, or besides some quite large; flat ones outside the row present; base of segment never with rhinaria; IVth segment two to four rhinaria on distal part; Vth without secondarv rhinaria, the primary rhinarium much elevated and bulging; VIth segment rather cylindrical, attenuated towards base, about 6 times as long as its maximum width; accessory rhinaria in two groups of which the basal one stands about halfway the segment, while the other stands beside the primary rhinarium.

In 1954 Delucchi erected the genera Enaysma and Epilampsis in an attempt to extend and clarify the generic concepts in the Derostenus Westwood-Chrysocharis Förster complex of the subfamily Entedontinae. As the type of Enaysma he designated Enaysma zwolferi Delucchi. Later in rhe same year (Delucchi 1954a) he revised the entire complex as he understood it in the Palaearctic region giving keys to the genera and species he included. Subsequently (Delucchi 1957) he supplemented his original description of the genus Enaysma and expanded his concept of it, adding Enaysma aenea Delucchi, Enaysma parva Delucchi, 1956, and two new species with a revised key to all the Palaearctic species then included by him in the genus. Recently Graham (1959) published a key to the British species in which he erected the new subgenus Pentenaysma, selecting as its type Eulophus latreillii Curtis.

During the summers of 1948 and 1949 the writer investigated the biology of the maple leaf cutter, Paraclemensia acerifoliella (Fitch), near Merivale, Ontario. Various aspects of the bionomics of the stages of the maple leaf cutter are summarized in this paper. Unpublished material in the annual reports prepared by Mr. J. J. de Gryse were kindly made accessible; data are quoted from them and acknowledged herein. Sincere thanks are extended to Howard A. Tripp for his assistance in recording data during field investigations.

The Royal Society Expedition to southern Chile, 1958-59, was concerned with a study of the area known as Archiplata (Kuschel, 1960), the southwest part of South America which formed an isolated land mass in the Tertiary and which is the part of the Neotropical region showing affinities with New Zealand, Australia, South Africa, the islands of the South Pacific, Atlantic and Indian Oceans, and the Juan Fernandez Islands.

Except for occasional references in the Annual Reports of the Forest Insect and Disease Survey of infestations of an aphid on caragana (Caragana arborescens Lam.) in Western Canada and a note on chemical control (Bradley, 1952), there is no published record known to the authors of the occurrence of the caragana aphid, Acyrthosiphon caraganae (Cholod.), in North America. MacNay (1953) summarized reports that severe infesrations of aphids, “probably mainly the caragana aphid”, occurred on caragana in 1952 in the East Kootenays of British Columbia, and at several places in Alberta and Saskatchewan. At some localities 100 per cent defoliation was reported.

Several investigators have shown that the composition of insect hemolymph varies considerably between various insect species (Crescitelli and Taylor, 1935; Pratt, 1950; Auclair, 1953 and 1959; Wyatt et al., 1956; Todd, 1958). It is possible that differences in the biochemistry of insect hemolymph could affect the nutritive value of host fluids. Therefore the feeding of the females of certain hymenopterous parasites on various hosts may affect also their fecundity and thus influence the establishment of imported parasites or the maintenance of indigenous parasites in certain habitats. Scambus buolianae (Htg.), an imported external parasite of the larvae of pine shoot moth, Rhyacionia buoliana (Schiff.), and possibly of other Lepidoptera species, was used to investigate the nutritional effect of various hosts on the fecundity of the females.

The European, or Essex skipper, Thymelicus (= Adopaea) lineola (Ochs.), was accidentally introduced into North America at London, Ontario, sometime before 1910 (Saunders, 1916). The history of its subsequent spread through southern Ontario and adjoining parts of Michigan and Ohio was reviewed by Pengelly (1961), who received the first report of extensive damage to hay and pasture crops by this insect in Ontario from the Markdale area of Grey County in 1956. A survey in 1958 (Pengelly, 1961) showed that the skipper “appeared to be present throughout the southern part of the province except for the Bruce peninsula and possibly the Windsor area. The northeasterly boundary appeared to he along a line from Midland, south around the west side of Lake Simcoe, east to Lindsay and south to Whitby.” The present author collected T. lineola larvae from the Belleville area for the first time in 1959.

Examination of the aphid parasites in the Canadian National Collection, Ottawa, provided evidence that several well-known European species are much more widely distributed than has been assumed. Material of the genus Monoctonus Haliday 1833 contained 11 females and 7 males of a species which was identified as Molonoctonus crepidis (Haliday 1834). A comparison with specimens from various European localities did not reveal any differences in the external morphology or in colour. This is the first record of this species from North America.

The Bruce spanworrn, Operophtera bruceata (Hulst), is most common in the mid latitudes of the North American Continent; in Canada it occurs from Newfoundland to the interior of British Columbia (Prentice, In Press) and has been reported from Vermont and Wisconsin in the United States (Craighead, 1950.) Three outbreaks of this insect have been recorded in Alberta. The first occurred in 1903 (de Gryse, 1925) and was apparently of short duration. The second reported by Wolley Dod (1913) occurred in 1913 and denuded hundreds of acres of aspen poplar. Heavy defoliation in the third outbreak became evident in 1957 (Brown, 1957) but an examination of Forest Insect Survey records revealed that population buildup began about 1951. The outbreak continued to expand until 1958 and began to decline in 1959; by 1961 populations were again low except for one or two isolated areas where moderate to low populations persisted. At the peak of the outbreak in 1958 approximately 50,000 square miies were moderately or heavily infested and many more lightly infested.

This paper includes descriptions of a new genus and a new species of the hymenopterous family Aphidiidae, which are primary parasites of aphids (Homoptera: Aphidoidea). The new genus, Boreogalba, belongs to the subtribe Trioxina and represents a primitive sideline of the Trioxys-Binodoxys group.

Feeding by a number of non-biting muscid species on blood made available by biting flies is known to occur in the Old World (Hammer, 1941; West, 1951). Species in several genera are involved, but particularly Musca. In North America, Hydrotaea tuberculata Rondani has been observed feeding in association with horse flies and stable flies (Tashiro and Schwardt, 1953). Often in these feeding associations, flies of the non-biting species not only visit abandoned wounds, but also wait near a feeding fly or attempt to feed simultaneously with it.

Hybridization has been studied in mosquitoes ever since caged colonies began to be maintained. Aedes particularly of the subgenus Stegomyia have been crossed variously at different times and by different observers. Anopheles species, particularly some of the subgenus Anopheles, have been hybridized with varying results. However techniques for inducing copulation developed in this laboratory (McDaniel and Horsfall, 1957) and used on Culiseta, Psorophora and many Aedes make possible combinations unlikely by chance in cages. Cage adaptation is not a prerequisite for success neither are precopulatory stimuli.