56 PROCEEDINGS OF THE ACADEMY OF [Jan., 



between this form and the type lies in the characteristic armature 

 of the dorsal surface of the stylets. The lateral spine is inserted 

 well towards the median line. On the outer lateral surfaces and a 

 little below the position usually occupied by the lateral spine there 

 is a row of prominent serrations. The position and course of this 

 row of serrations may be seen in fig. 6 of PI. IV. There are two well- 

 developed apical setse which are carried prominently divaricate. Of 

 these two, the outer is a little over half as long as the inner aQ,d is 

 ornamented on its outer surface with minute spines, its inner surface 

 bearing the usual hairs. Herrick's statement, "inner two-thirds as 

 long as the outer," is undoubtedly another case of reversed propor- 

 tions. The longer seta is plumose. The delicate innermost setse 

 are as long as the outer and generally curved as in fig. 6, PI. IV. 

 The outermost setse are very heavy, rather blunt and delicately 

 plumose on their inner surface only. About the base of each there 

 is a f circle of long serrations. 



The first antennae of the female (fig. 7, PI. IV) are eight-jointed. 

 They are only half as long as the first thoracic segment and are 

 carried at right angles to the median line, as is the case with practically 

 all of the Cydopidce. The segments taper rapidly, the distal one 

 being but one-quarter as wide as the first at its line of juncture with 

 the second. The fourth segment is the longest. The two distal 

 segments are slightly bent forward in life (fig. 5, PI. IV). Herrick 

 states: "The basal joint with a small semicircular series of fine 

 bristles." This is not a characteristic of this species, but of the 

 entire genus. Miss Byrnes' description is this: "The antennae 

 contain but eight segments; they are short and are characterized 

 by two well-developed setae." The fifth segment bears a well- 

 developed sense-club (fig. 7, PI. IV). This is somewhat different 

 from Schmeil's figure of this organ for the type form. In the speci- 

 mens that I have examined I find it to be rather more slim and 

 spear-shaped than "club-shaped" as in the type. It suggests the 

 form of the corresponding organ in C. bicuspidatus Claus (PI. II, 

 fig. 5). Many of the setse of the first seven segments are delicately 

 plumose, but those of the terminal segment are, as far as I have been 

 able to observe, quite bare. Along the line of the distal third of the 

 third segment (fig. 7, PI. IV) I have repeatedly noted what appears 

 to be the beginning of the segmentation of another antennal joint. 

 However, I have never observed a specimen of "var. poppei'' with 

 nine-jointed first antennae. The semicircle of fine bristles at the 

 base of the first joint is unusually prominent. 



