52 BULLETIN OF THE LABORATORIES 



A somewhat larger form, also found in Minnesota, has more slender 

 claws and seems to lack the spine on the last joint of the foot. The 

 shape is otherwise the same. 



The cast-off shell of still a different form, in which there is an in- 

 dication of segmentation near the anterior of the lorica,was once seen. 



GENUS SALPINA, Ehr. 



Somewhat resembling Euchlanis, but having spines upon the front and posterior 

 margins of the laterally compressed lorica. There is a median area above, which 

 is less perfectly indurated than the sides, giving rise to two ridges. The foot is 

 short, three-jointed, and bears two lanceolate claws. The eye is single and the 

 ciliation of the trochal disc rather strong. The maxtax is large and the digestive 

 tract well differentiated. Water-vascular system with two or three beaker-cells on 

 either side. The Qgg is carried about with the parent after extrusion. 



Salpina affinis, sp. n. 



{Plate II., Fig. 4-) 



This species is so allied to 6". 7)zucronata, Ehr. that it is with some 

 hesitation that a new name is proposed. While agreeing in most 

 characters, it differs from that species in having the upper pair of 

 anterior spines much longer than the lower and curved downward and 

 in having the lower pair of posterior spines much longer than the 

 single upper one and curved upward. S. niucronata is said to 

 measure but .15 to .16 mm., while our form is .22 to .24 mm. long and 

 .10 mm. wide. The anterior spines measure .045, length of claws, .06 

 mm. The whole shell is granulated and there is a band in front, set 

 off by a distinct line. There is a sensory tube which bears a bundle 

 of cilia at its end, and which usually projects from between the two 

 dorsal spines of the lorica. The eye is lunate and seated on a very 

 large, almost spherical ganglion. The maxtax is very large and opens 

 into a slender oesophagus. The stomach is glandular and saccate. 

 The very large egg is ventral. No careful, study was made of the 

 viscera. Minneapolis, May. 



The species of the genus, aside from those mentioned, are S. 

 spinigera, Ehr., S. brevispina, Ehr., S. ventralis, Ehr., S. bica7'inata, 

 Ehr, S. redunca, Ehr., S. dentatus, Duj., and S. polyodonta, Schm. 

 There is reason to suppose that several of these are but varietal forms. 



