STATE GEOLOGIST. 225 



segment of the outer ramus extending into a large lanceolate process; 

 ova sac long-elipsoidal reaching to nearly the end of caudal setae. 



This species prefers running water or estuaries of streams. Crow 

 river, Meeker county, and a brook between Minneapolis and St. Paul. 



NOTE ON CANTHOCAMPUS. 



Claus says (Freilebenden Copepodeyi, p 121) that he could not find the 

 coiled "shell gland" in Canthocampus, though it is described by Leydig. 

 I have found it in a European species, {C. miniUus?) and think it con- 

 stant. Canthocampus also has a singular area of nervous hairs upon 

 the forehead, and in the same situation, pits which seem rudimentary 

 eye-spots and sometimes appear to be pigmented. The pentagonal area 

 mentioned is bounded by a raised line. 



CYCLOPID^ 



Contains five genera, viz. : Thorellia, Cijclojjf^, Olthona, Lophoph- 

 orus aiid'Ci/cIopina; passing, by the genera Misophria and Pseudocy- 

 clops, into the Calanidce or marine copepods. The afiinities of these 

 little studied genera need farther study, as they are very interesting, 

 the question being still open in how far the cj^clopoid forms are altered 

 by adaptation to saline habitat, if such an adaptation takes place at all. 



The following is Brady's definition: 



Cephalothorax ovate and usually much more robust than the abdo- 

 men; anterior antennae seldom longer than the cephalol:horax, those 

 of the male alike on both sides and modified for the purpose of clas^D- 

 ing: posterior antennae branched (i. e. jDalpus Avanting); palps of 

 mandibles and maxillae usually well-developed; foot-jaws mostly less 

 developed than in Calanidce ; first four pairs of feet as in Calanida', 

 fifth pair rudimentary, alike in both sexes, and usually one -jointed; 

 ovisacs two. 



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