Supposed New Species of Acinetan. 13. 
transverse to the axis of the jaw. In the selenodont Diplarthra, 
where the thrust is transverse to the line of the jaw, the cres- 
cents are longitudinal. That similar effects should accompany 
similar movements in two groups of Mammalia so widely sepa- 
rated as these two, is strong evidence in favor of the belief that 
the two facts stand in the relation of cause and effect (Fig. 9, Figs. 
b and d). ` 
DESCRIPTION OF A SUPPOSED NEW SPECIES OF 
ACINETAN, WITH OBSERVATIONS ON ITS 
MANNER OF FOOD INGESTION AND 
REPRODUCTION. 
BY ©. C. NUTTING. 
PoDOPHRYA COMPRESSA Nutting. 
[)ESCRIPTION :—Body illoricate, quadrate, wider anteriorly ; 
length from two to five times the greatest width ; compressed, 
about three times as wide as thick; the anterolateral corners 
occupied by rounded prominences, each bearing a fascicle of many 
suctorial tentacles which, when fully extended, are more than half 
the length of the body, and spiral or spirally marked when 
retracted ; posterior portion of body rapidly narrowing to meet 
the very short thick pedicle which is furnished with a sucking 
disk at its distal end; parenchyma densely and evenly granular 
contractile vacuole single, anterior ; endoplast oval. 
Length of body, 1-277” to 1-140”. 
Habitat. Fresh water. 
The above-described species has recently been numerous in a 
fresh-water aquarium in the Biological Laboratory of the State 
University of Iowa, where it was first noticed by Professor S. 
Calvin, who kindly delegated its investigation and description to 
the writer. 
? 
In general appearance it somewhat resembles certain species of 
the genus Acineta, but the absence of any indication of a lorica 
excludes it from that group, and it is hence, with some doubt, 
placed in the genus Podophrya, with which it agrees in possessing 
distinctly capitate, fasciculated, suctorial tentacles only. It is 
