1887.] NATURAL SCIENCES OF PHILADELPHIA. 123 



varies considerably with the inclination of the horns, a difference of 

 iVoo of f^n iiich being observed in different specimens having the 

 same length, ^^^ to jfj of an inch being common. The transverse 

 diameter is always about half that of the broad diameter, narrow- 

 ing gradually to the cylindroid mouth. The hexagonal cancella- 

 tions are about ^o o^ of ^^ iiich in diameter, their regularity varying. 

 The sarcode in the specimens observed occupied not more than half 

 the interior capacity of the shell, pyriform in shape, with never 

 more than three pseudopods projected. A current of Avater directed 

 into the mouth of a shell, caused, in one instance, the instant retrac- 

 tion of two long pseudopods, and the carrying of the whole mass of 

 sarcode to the fundus of the shell. 



The shell of Nehela collaris, Leidy, is obovate in the broad aspect, 

 and the fundus is edged with what looks like a row of tiny bubbles. 

 In the lateral aspect, the shell is generally pyriform, with an acute 

 fimdus. The length of the shell is about ^Iq of an inch, and its 

 greatest breadth 3^77, the proportions varying but slightly in many 

 specimens observed. The sarcode is the same as in Dijjiugia cornuta^ 

 and many specimens were observed with the sarcode formed into a ball 

 in the center of the shell. The sarcode of all specimens seen, con- 

 tained numerous brown granules and brown or greenish food-balls, 

 similar in color to the diatoms and desmids associated with all these 

 Rhizopods. 



