STATE GEOLOGIST. 155 



all 3-jointed and are peculiar in their armature. The fifth foot is 

 obscurely 3-jointed, the second joint bearing a short spine and the 

 terminal joint two spines of varying length. The stylets are once 

 and a half as long as the last segment and are peculiarly excavated 

 for more than the lower third, from the point where the lateral 

 spine is situated. The outer terminal seta is short, the others being 

 sub-equal and also short. The opening of the spermatheca is elong- 

 ated, oval. The antenna of the male is divisible into five regions^ 

 the third being formed by the thickening and coalescing of four or 

 more segments. 



Antennae 14- jointed. 



Sp. SO. Cyclops insignis, Glaus. 



The two forms here belonging might be considered atavic varie- 

 ties of Cyclops pulchellus. Brady's figures and description of his 

 C. insignis (= C. lubbockii) agree almost exactly with what Reh- 

 berg says of Cyclops helgolandicus (Abh. v. naturw. Vereine zu 

 Bremen, vii. 1. pp. 62 — 64). Rehberg regards that species as an 

 atavic sub-species or variety of C. pulchellus. With C. insignis,^ 

 Claus, the case seems to be different. The occurrence of this species 

 is not conditioned by marine influence. I found it abundant about 

 Leipzig, Saxony. The differences between it and the C. insignis of 

 Brady are, as the latter says, very slight. Figs. 11 — 14 of plate T 

 are drawn from Leipzig specimens, from osmic acid preparations. 

 The first foot, outer ramus, has three external spines on the distal 

 segment, two setae at the end, and three within; the inner ramus 

 has one internal seta, a spine and a seta terminally, and three ex- 

 ternal setse on the distal segment. The outer terminal segment of 

 the fourth foot is like the first; the inner one has only two external 

 setffi. The external setse of the caudal stylets exceed half the length 

 of the stylet and are pectinate. The fifth foot has a- short basal 

 joint armed with a single seta, the second joint being slender and 

 armed with two unequal setae. The gathering above mentioned, 

 taken near Leipzig, Dec, 1881, contained scarcely a female among 

 scores of males in various stages of development. This is so con- 

 trary to what is expected that, notwithstanding the apparently 

 good characters on which the species is founded, an uncertainly 

 exists in the mind of the writer as to the permanent adult charac-^ 

 ters of this species. 



