i5 



to the thin marginal rim and about equidistant from the fourth and 

 fifth spines on their respective sides of the body. These eyes are 

 rounded and less than .01 mm. in diameter. 



There are three pairs of dorsal spines. The first pair is situated 

 on the cephalic region, one on each side, a short distance mesad 

 from the eyes. The second pair is situated one on each side of the 

 basal abdominal region, apparently on the third abdominal segment. 

 These two pairs of spines are very minute, and require a high power 

 objective for their detection. The third pair of dorsal spines is 

 much larger, and situated one on each side of and a little anterior to 

 the operculum of the vasiform orifice. 



On the ventral side of the body (Plate II, Fig. 4) are the legs, 

 antennae and mouth parts. The entire length of a leg (Plate III, 

 Fig. 9) when straightened is about one-half the width of the body. 

 The coxa? are short and stout, and near the base of each of the two 

 posterior pairs on the inner side is a spine about as long as the 

 diameter of the coxa. These spines are usually directed inward and 

 backward. The trochanters are short ; those of the anterior pair of 

 legs are sub-cylindrical, about one-third as long as wide ; those of 

 the two posterior pairs of legs appear more or less hoof-shaped, and 

 each of the six trochanters bears a short spine anteriorly. The femur 

 is about twice as long as the coxa and trochanter together, sub- 

 cylindrical in form, tapering toward its outer end. The tibia is a 

 little longer than the femur and more slender, in each of the two pos- 

 terior pairs of legs bearing on its outer side near its base a spine as 

 long as the whole tibia itself. This extends obliquely outward, and 

 is usually curved near its tip. In addition, all three pairs of tibise 

 bear a number of minute spines. The tarsus, which consists of a 

 single segment, is short, knobbed at the tip, with a stout curved 

 spine about half as long as that borne on each of the two posterior 

 tibiae, arising on its outer side near its base. 



Half way between the first and second pairs of legs in the mid- 

 dle line of the body is a conical fleshy papilla — the rostrum — from 

 an opening in the apex of which, surrounded by four minute spines, 

 the mouth setae protrude. The length of the setae varies, but when 

 bent backward they usually extend to a point between the hind 

 coxae and the caudal margin of the body. In front of the rostrum 

 is a prostomial plate or shield, subovate in form, the broader end 



