156 



University of California Publications. [Entomology 



generic arrangement as given by Professor Becker in his 

 monograph of this family, Berliner entomologiscJie Zeitschrift, 

 1896, Tafel vii, Fig. 19 (reproduced here in Fig. 105, b). The 

 two hairs at the center of the field posterior are so small, how- 

 ever, that they might be overlooked in a casual examination. 

 (Fig. 105.) Lcnigth, 3.75 to 4 mm. 



Egg.— White obovate, somewhat irregular in outline, with- 

 out definite markings; clothed with hairs about the smaller 

 end, usually sparsely; attached by the larger ends to floating 

 bits of vegetation or puparia. (Fig. 102.) 



FKi. 102. Esrgs of Ephydra wiUhrir. 



Larva. — Length, 10 to 12 mm. with the anal siphon and its 

 two tubes extended. Length of siphon, 3.5 mm. Densely and 

 uniformly pubescent, excepting a number of small, very dense 

 clusters of black hairs irregularly arranged on the last six 

 segments, dorsad. Abdominal segments with eight pairs of 

 false legs, non-articulated, ventral exterior end of each with 

 two rows of transverse, curved hooks ; all but last pair with 

 first row containing four hooks, second five ; behind these are 

 three or four irregularly arranged. Each leg of the last pair 

 bears thirteen claws in three irregular rows, the first two with 

 three claws each and the third with seven smaller ones. Mouth 

 parts composed chiefly of a pair of large median or foot hooks, 

 provided with smaller, hook-like processes on the ventral sur- 



