ENTOMOSTRACA OF MINNESOTA. 121 



short, especially the last segment, with is toothed behind; stylets very 

 short. The antenna) are much shorter than the first segment, 11- 

 jointed. The maxillipeds are very small. All the feet are armed 

 with a row of very large teeth or lanceolate spines down one side; fifth 

 foot one-jointed, with three spines, the outer being smooth, the others 

 spiny; egg-sacs variable, narrow, appressed; eggs large, color usually 

 dark. The animal moves like Canthocamptus, and is able to progress 

 out of water better than other species. The following measurements 

 will give an idea of the proportions: Length 1.26 mm., thorax 0.76 

 mm., abdomen 0.41 mm., stylets 0.06 mm., longest seta 0.34 mm., an- 

 tennae 0.28 mm., width of thorax 0.44 mm." 



Measurements of another specimen are as follows: Length 1.1 mm., 

 thorax 0.65, first segment 0.33, abdomen 0.45, longest seta 0.6. 



The male is more slender (0.93 mm. long) and the longest caudal 

 seta greatly exceeds in length the whole abdomen. The antennae are 

 strongly modified. 



* Cyclops finibriatus Fischer. 



Plates XVII, Figs. 8, 9; XXI, Fig. 11; XXV, Figs, 9-14. 



Herrick '82 (crassicornis), and '84 and 'STJ; Turner '92; Marsh '93. [The manuscript 

 gave not the slightest hint as to date or reference in the following, given in the 

 order of the manuscript:] Mueller (crassicornis); Fischer; Sars (crassicornis); Hel- 

 ler (gredleri); Fric (pauper); Uljanin (crassicornis); Brady (crassicornis, and 

 fimbriatus); Rehberg (poppei, and fimbriatus); Daday (finibriatus, and margoi); 

 Vosseler; Scbmeil; Richard. 



A small species (0.8 to 0.9 mm.). Thorax oval, not greatly ex- 

 panded, angles of segments rather prominent. First thoracic seg- 

 ment forming about half the length of the cephalothorax. Abdomen 

 rather long and thick, terete, about as long as the thorax. Last two 

 abdominal segments armed with a row of spines at the, caudal margin. 

 Caudal stylets twice as long as the last abdominal segment. 



A series of small teeth in a longitudinal series generally ornaments 

 the stylet. Lateral spine small. The outer apical spine strong, the two 

 median setae long, spinously armed, inner two-thirds as long as the 

 outer. Inner apical seta weak and short, pectinate. Antennae shorter 

 than the first segment, 8-jointed; formula: — r-^-^rr, the basal 

 joint with a small semicircular series of fine bristles. Antennules 

 short, apical segment short with but two strong sette and several 

 smaller ones. Feet armed with spines and bristles. Formulae for 

 fourth foot as follows: 



!ex. 2 spines. Tex. 1 seta, 



ap. 1 spine, 1 seta. Inner ramus \ ap. 2 spines, 



in. 4 setaj. [in. 2 setae. 



I By a curious mistake in this paper on p. 14, ttie reference to Plate YII, Fig. 2, is placed opposite 

 C. fimbriatus and not, as it should be. opposite C. phaleratus. This mistake was then reproduced in 

 the description of plates, p. 56. 



