52 PROCEEDINGS OF THE ACADEMY OF [Jan., 



over, but the one condition passed into the other. In addition, the 

 anterior end was constantly being wrinkled and distorted, and little 

 pseudopodia-like processes were protruded and withdrawn. 



Host: Spiroholus. But one individual examined, which contained 

 seven or eight gregarines, none less than 500 microns in length. 



Locality: Raleigh, N. C. 



Echinomera hispida AimL' Schn. 



Echinocephalus hispidus Schneider (187.5), p. 593, PL 16, figs. 36-40. 

 This gregarine was found in four out of thirteen individuals oiLitho- 

 hlus foirijxitus collected at Wyncote, Pa., and Raleigh, N. C, but it is 

 much commoner at Cambridge, Mass. 



Echinomera microcepliala Leidy. 



Gregarina microcephala Leidy (1889), p. 11, 1 fig- 

 Our knowledge of this form rests upon a very short description given 

 by Prof. Leidy. It is very much like Echinomem hispida, and is accord- 

 ingly placed in that genus, but retained as a distinct species. 



The total length is 350 microns; greatest width 100 microns. The 

 protomerite is 12 microns long by 40 microns wide. 

 Host: Hoplocephala bicornis. 



Trichorhynchus pulcher Aime Schn. 



Trichorhynchus pulcher Schneider (1882), p. 438, PL 13, fig. 14. 

 Gregarina megacephala Leidy (1889), p. 11, 1 ng. 



This form is well described by Aime Schneider, whose figure also is 

 excellent giving a very accurate idea of the actual animal. Schneider, 

 however 'gives no dimensions, while Leidy says that the dimensions 

 vary from 420-750 microns, these figures agreeing very closely with 



those which I obtained. 



My own observations on this species show it to be an active, very 

 polymorphic gregarine, with the ability to undergo extensive altera- 

 tions in shape. Thus, the anterior end of the protomerite, normally a 

 blunt curve, frequently protrudes in a long tongue-shaped process. 

 The peristaltic movement, so frequently displayed by gregarmes, iw, 

 in this species, pass forward as well as l^ackward. This inchcates that 

 here the contractile elements are capable of operating as weU m one 

 direction as another, which is certainly not the case in most polycystid 



o;regarines. , , ,^, •, ,^ 



Fusion, preparatory to encystment, was seen to take place head to 



head." 



