56 PROCEEDINGS OF THE ACADEMY OF [Jan., 



dichotomoiisly branched lobes. Contents hyaline. Easily detached. 

 In the small animals, making up nearly one-half the total length; in 

 the adults, from one-fourth to one-fifth of the total length. 



Protomcrite: In the young, knob-shaped, with the transverse and 

 longitudinal diameters al^out equal. In the adults, hemispherical, with 

 the transverse diameter twice as great as the longitudinal. 



Deidomcrite: Conical, Avith a pointed posterior end. Usually a shoul- 

 der at the septum. Subject to considerable alterations in shape, being 

 at one time longer and narrower, at another shorter and broader. 



Epicytc: About 3 microns thick [in the larger individuals. Longi- 

 tudinal striations could not be made out. 



Sarcocyte: ?. 

 ■ Eniocyte: Absolutely opac^ue in the larger animals. Much more 

 nearly transparent in the smaller. 



Nucleus: Only apparent as a light oval area, usually l3dng diagonally 

 across the deutomerite. 



Dimensions: The largest sporont seen was 485 microns long by 105 

 microns broad. Leidy gives 600 microns for the length of a cephalont. 



Host: Scolopocryptops. Not rare. Infection usually moderate, from 

 15-30 parasites per host. 



Loccdity: Wyncote, Pa., Raleigh, N. C, and Walhngford, Pa. 



Apparently, in this gregarine, the septum tends to disappear. It is 

 much more evident in some cephalonts than in others, and in one spo- 

 ront seen no septum could be made out, and the entocyte of the proto- 

 merite was not distinguishable from that of the deutomerite. 



Doliocystis rhyncobli sp. n. 



Porter (1897«), p. 8, PI. 3, figs. 37-53. 



This form is described, but not named, by Porter, and the figures given 

 are scarcely diagnostic enough to determine the correct genus. Its 

 habitat, the intestine of the marine worm Rhyncobolus americanus Ver- 

 rill, renders it probable, however, that the parasite belongs to the genus 

 Doliocystis, and the specific name rhyncoboli may appropriately be used. 



Porter describes it as a tricystid, but says : "The conical base of the 

 epimerite is continuous with the contents of the anterior portion of the 

 protomerite, for there is an orifice through the cuticular wall of the pro- 

 tomerite, and the base of the epimerite is composed of protoplasm very 

 similar to that of the protomerite." 



But such an intimate union between the protoplasmic parts of pro- 

 tomerite and epimerite is not known to exist in gregarines. It may 

 therefore be suggested that that part of the animal which Porter took to 



