THE CANADIAN ENTOMOLOGIST. 185 



DESCRIPTION OF THE LARVA OF DELPHASTUS 



FUSILLUS, LEG, WITH NOTES ON THE 



HABITS OF THE SPECIES. 



BY W. E, BRITTON, NEW HAVEN, CONN. 



In collecting insects at Poquonock, Conn., July i8, 1904, my assis- 

 tant, Mr. B. H. Walden, found coccinellid larv?e feeding upon a species of 

 Aleyrodes which is probably undescribed, and fairly common there upon 

 the leaves of hazel, Corylus Americanus. These larvae were brought to 

 the laboratory, and were fed upon Aleyrodes vaporurioriiin, Westw., 

 which they ate greedily. On July 23rd two had moulted ; on the 28th, 

 these had changed to pupae, and the third larva had begun to devour one . 

 of the papae — his aleyrodid food supply having become exhausted. 



From the uninjured pupa an adult emerged August 2nd, and the 

 remaining larva pupated August 1st, the adult emerging August 8th. The 

 adult is a small black beetle, about 1.5 mm. in length. Specimens sent to 

 Washington were determined by Mr. E. A. Schwarz as Delphastus pusillus, 

 Lee. This species has been placed in the genera (Eneis by LeConte, and 

 Cryptognatha, by Crotch and Horn, but Casey has erected the genus 

 Delphastus* on account of the difference in structure. Delphastus now 

 includes four American species. 



In searching the more accessible literature of American entomology, 

 I fail to find any description of Delphastus pusillus, or any reference to 

 the feeding habits of the species, though the habits of most coccinellid 

 larvae are known. I therefore give the following description and notes as 

 an addition to the knowledge of this species, though it is possible that a 

 description of this larva has been published, and that I have overlooked it. 



When first taken, this larva was uniformly light gray or dirty white in 

 colour, with dark spots on the dorsum of the first thoracic segment. After 

 moulting, the general colour was much darker, and the following description 

 applies to the final stage of the larva before it changed to a pupa. 



Larva : Length, about 4 mm.; greatest width, about 2 mm. Ground 

 colour gray or dirty white, with a white median line extending the entire 

 length of thorax and abdomen. There are two pear-shaped black spots 

 on the front of the dorsum of the first thoracic segment, one on each side of 

 the median line. Just back of these spots are a pair of larger dark gray 

 or lead-coloured spots, one on each side of and close to the median line. 

 A lead-coloured area appears on the lateral margins of the segment. 



*T. L. Casey, Journal New York Entomological Society, Vol. VII., p. iii. 

 May, I905' 



