00 



6 AGRICULTURAL EXPERIMENT STATION. 



it is almost colorless, except the eyes and four air sacs, which 

 are black, but when put in alcohol it turns to creamy white. The 

 head is sub-conical in shape, the antennae pendant at the front, 

 with four very lon^ spines at the apex of each. The thorax is 

 broader than the abdomen and bears on its dorsal surface two 

 black air sacs, arranged side by side. The abdominal segments 

 are almost of equal length, tapering posteriorly, and with the 

 seventh segment bearing a second pair of air sacs ; the anal seg- 

 ment has on its ventral surface a fan-like arrangement of long 

 feathered hairs issuing from a serrated ridge, and near the end of 

 the segment is a weakly chitinized. transverse plate with small 

 teeth directly anteriorly. The four trachael gills are of moderate 

 length, dilated centrally and four long hairs, two of which are 

 feathered, are directlv above the o-ills. 



Habits of the Baiiy Stages. 



Mr. Grossbeck believes that this insect winters in the larval 

 stage, but we have no positive evidence on this point. He also 

 believes that the transparent texture is protective and shields the 

 larva from its natural enemies. As a basis for this belief he cites 

 the occurrence of hundreds of these larvae near Paterson, N. J., 

 October 3, in a pool in which predatory aquatic insects were 

 abundant and in which no other mosquito larvae occurred. The 

 pool is normally a large piece of water, but had been reduced by 

 drought to a diameter of about eight feet and a depth of one foot. 

 In this all the inhabitants were now concentrated and Sayomyia 

 appeared to remain undisturbed. Normally Culcx pipiens, C. ter- 

 ritans and the species of AnopJicics breed in the shallow edges of 

 the small pond when it is full ; but these larvae had all disap- 

 peared, probably eaten by the water tigers, which were plentiful. 

 In life the larva readily escapes detection in even clean water. 

 In alcohol it becomes opaque and of a dull white color. The 

 larvae are predatory, but not very rapacious, a few Cidex larvae 

 lasting a long time in a well stocked jar. 



Specimens were found full grown at Arlington, May 2d, in a 

 pool with Culex canadensis and Aedes fusciis and adults were 

 obtained May 7th. July 14th, Mr. Seal sent in specimens from 

 Delair and these yielded adults July 22d and 23d. The species 

 is apparently common at times from Mr. Seal's report. July 

 20th, a single specimen occurred with small Anopheles and Cidex 

 tcrritans near Paterson. There were also two small Psorophora 

 which were overlooked, and four days later, returning from field 

 work, only the Psorophora remained; fifty-three Anopheles and 



