100 GEOL. AND NA.T. HIST. SURVEY OF MINNESOTA. 



Hoek '78 (brevicaudatus); Brady '78 (pulchellns, and strenuus); Heriick '84; 

 Daday '85 (claudiopolitanus, hungaricus, paradyi, elongatus, and strenuus); Vos- 

 seler '86 (lucidulus, bodamicus, and strenuus); Sostaric '88 (quadricornis); Thall- 

 witz '90 (lucidulus); Lande '90 (vicinus, and strenuus); Richard '91; Brady '91 

 (abyssorum, vicinus, and strenuus); Schnieil '91 and '92. 



This species is said to be one of the most abundant on the continent 

 of Europe and assumes a great variety of forms whose relations are 

 far from clearly understood. 



The cephalothorax is large, and the fourth and fifth segments pro- 

 ject laterally. The abdomen is five-eighths as long and tapers distally. 

 The stylets are slender, divaricate, longitudinally ridged above and 

 about as long as the last three segments of the abdomen. The two 

 median setee are relatively short, the inner apical being as long as the 

 stylet and twice as long as the inner apical or more. Lateral seta 

 small, not far from the end. The antennse reflexed scarcely reach the 

 base of the third segment. The fifth foot is two-jointed, the basal seg- 

 ment being small, nearly quadrangular and armed with a short ciliate 

 seta. The apical segment is longer, with one long apical seta and a 

 lateral spine. Length 1.5 to 2.5 mm. Schmeil observed a specimen 

 3.2 mm. long. Schmeil unfortunately places no reliance on the arma- 

 ture of the feet, which, as Marsh also has shown, are of great import^ 

 ance and are fairly constant, and his figures and descriptions help but 

 little in solving the perplexities of this multiform species. In this 

 we are at present the less interested in that the species has not as yet 

 been recognized in America. 



Brady gives greater detail and fails to offer valid reasons for sepa- 

 rating (J. abyssorum and C. vicinus from strenuus, though he inclines to 

 believe C. abyssorum a deep sea variety of C. vicinus— C. pulcliellus of 

 his monograph. 



The formulae for the feet in abyssorun are as follows: 



FiKST Foot. 



!ex. 2 spines. (ex. 1 seta, 



ap. 1 spine, 2 setse. Inner ramus < ap. 1 spine, 1 seta, 



in. 3 setfe. (. in. 3 setse. 



Third Foot. 



fex. 2 spines. ( ex. 1 seta. 



ap. 1 spine, 1 seta. Inner ramus < ap. 1 spine, 1 seta, 



in. 4 setfe. (.in. 3 setse. 



Fourth Foot. 



("ex. 2 spines. (ex. 1 seta. 



Outer ramus < ap. 1 spine, 1 seta. Inner ramus < ap. 2 spines, 



(in. 3 setae (4 setaj?) (in. 2 sette. 



The only difference of importance between the two species seems to 

 be the shorter antennte of C. vicinus. 



