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 egg is carried about with the parent after oxtrusion. 
Salpina affinis, sp. n. 
(Plate II. , Pig. 4 -) 
This species is so allied to S. muc 7 'onata^ 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. nmcronata 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. bica 7 '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. 
