464 



POPULAR SCIENCE MONTHLY 



Fig. 



13 Last Segment of 

 Larva Profile. 



— and almost black in color. All were secured and taken into camp 



for further investigation. 



Close observation of the larvae showed that besides being much 



larger (12-14 mm. long instead of 5-7 mm.) they differed in many 



other particulars from the larvae of Anopheles (see Fig. 12). In pro- 

 portion to the rest of its body^ its head is 

 larger than the head of Anopheles. It does 

 not turn its head upside down when feed- 

 ing as does Anopheles. Its mandibles are 

 strikingly large and powerful and are prom- 

 inently toothed. It lacks the frontal tufts 

 or brushes which are conspicuously present 

 in Anopheles, and its antennae, which extend 

 directly forward parallel with the sides of 

 the head, are much longer and more slen- 

 der, and are tipped each with three hairs 

 of equal size. The thorax is broadly ellip- 

 tical 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 (see Fig. 13), are more profuse in Eucorethra than 



in Anopheles, especially the ventral tuft which in Eucorethra occupies 



nearly the whole segment. Only two anal papilla are present, while 



Anopheles has four. 



A few days before the author returned to Boston, several larvae died 



and three changed to pupae. The pupa resembles that of Culex (see 



Fig. 14) rather than of. Anopheles and its respiratory siphons are of 



the same shape as those of Culex. 



When stretched out at full length, 



the pupa measures ten mm. 



On reaching home, the new 



wigglers, eighteen 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. The act was 



witnessed on several occasions. 



The larva would grasp its adver- 



FiG. 14. Pupa Eucorethra under woodi. 

 Original Drawing. 



