AiGisT 7, 1903.] 



SCIENCE. 



183 



section of Penobscot County, and were dis- 

 covered in a spring of water from which a 

 crew of lumbermen were getting their water 

 supply. A few days later, I found other 

 larvffi of the same species in a similar spring 

 about eight miles distant, though in this case, 

 as the spring was not in use, it was covered 

 •with a coating of ice an inch thick. The 

 temperature of the water at the bottom (it 

 was about two feet deep) was 42° F. 



At first sight this larva would be taken for 

 an Anopheles of extraordinary size, as it is of 

 the same general shape, and when the water 

 ■was cleared of ice, it lay just beneath and 

 parallel to the surface, breathing through a 

 short respiratory siphon, as is characteristic ' 

 of the larvse of Anopheles. In this spring a 

 barrel had been sunk and in the fifty gallons, 

 or thereabouts, of water which it contained 

 there were twenty-five larvae. They were all 

 of about the same size — 12 to 14 mm. long- — 

 and almost black in color. All were secured 

 and taken into camp for further investigation. 

 Here they were Ivcpt for thirteen days at a 

 temperature varying from 32° at night to 

 65° or 70° during parts of the day — an aver- 

 age temperature of about 45° F. 



Close observation of the larvaa now showed 

 that besides being much larger (12-14 mm. 

 long instead of 5-7 mm.) they differed in 

 many other particulars from the larvaj of 

 Anopheles. In proportion to the rest of its 

 body, its head is larger than the head of 

 Anopheles. It does not turn its head upside 

 down when feeding as does Anopheles. Its 

 mandibles are strikingly large and powerful 

 and are prominently toothed. It lacks the 

 frontal tufts or brushes which are conspicu- 

 ously present in Anopheles, and its antennae, 

 which extend directly forward parallel with 

 the sides of the head, are much longer and 

 more slender, and are tipped each with three 

 hairs of equal size. The thorax is broadly 

 elliptical and is much wider in comparison 

 with its abdominal segments than is the 

 thorax of Anopheles. The sides of the thorax 

 and the abdominal segments bear fanshaped 

 tufts of hairs, not plumosed as in Anopheles. 

 The tufts on the last segments, both dorsal 



and ventral, are more profuse in Eucorethra 

 than in Anopheles, especially the ventral tuft 

 which in Eucorethra occupies nearly the whole 

 segment. Only two anal papillffi are present, 

 while Anopheles has four. 



A few days before I returned to Boston, 

 several larva; died and three changed to pupse. 

 The pupa resembles that of Ciilex rather than 

 of Anopheles and its respiratory siphons are 

 of the same shape as in Cider. When 

 stretched out at full length, the i)Ui)a meas- 

 ures ten mm. 



On reaching home, the new wigglers, eight- 

 een in number, were put into a quart jar 

 which was placed near a window where it 

 would receive the sunlight for two hours each 

 morning. The temperature of the water now 

 averaged about 70° F., and with this change 

 the larvae developed a new trait — they began to 

 eat each other up. I witnessed the act on 

 several occasions. The larva would grasp its 

 adversary just forward of the respiratory 

 siijhon with its powerful mouth parts, and 

 working the tail in first it would gradually 

 swallow its victim, shaking it now and then 

 as a terrier would shake a rat. 



After losing a part of my stock in this way, 

 those that remained were separated, and each 

 individual was placed in a small bottle by 

 itself. Eventually, I succeeded in rearing a 

 number of males and females. The pupal 

 stage of this insect varies from five days and 

 niiie hours to six days and ten hours. The 

 adult resembles Anopheles in having maculated 

 or spotted wings, but is much larger and meas- 

 ures eleven millimeters in length. Its mouth 

 parts, however, are not adapted for biting. 

 A full description of the imago is soon to be 

 recorded by Mr. D. W. Coquillett of the Na- 

 tional Museum by whom the name above men- 

 tioned was given. 



Drawings were made of all the different 

 stages and on May 20, 190.3, they were sent 

 to Dr. L. O. Howard, chief of the Division of 

 Entomology, at Washington. 



On July 24, word was received from Dr. 

 Howard that a new genus had been made for 

 the insect and that Mr. D. W. Coquillett had 

 named it Eucorethra undenvoodi. I was also 



