676 A NEW KNDOPARASITIC^COPEPOD, 



The body-cavity (liiBmoco?!) is more or less filled by branched, 

 connective tissue cells, in some places more so than others. Cor- 

 jiuscles of two kinds are present in the crolomic fluid; small, spheri- 

 cal, hyaline corpuscles about 3/x in diameter, with intensely stain- 

 ing nucleus, and larger forms with more opaque cytoplasm and 

 vesicular nucleus, and varying in size from 8 to \5fM. These latter 

 are irregular in outline, and are probably amoeboid. 



From place to place along its length, the alimentary canal is 

 slung to the dorsal and ventral body-wall by bundles of clear fibres 

 of some thickness (about 1/x), which closely resemble plain muscle- 

 fibres, but are devoid of nuclei. 



Alimentary Canal. — Within the mouth is a small chitin-lined, 

 buccal cavity (Fig. 15), from which the oesophagus passes directly 

 dorsad (Fig. 2), to the centre of the body, and there opens into the 

 digestive tract, which, divided by three constrictions into four eom- 

 IDartments, extends backward in a straight line through the trunk, 

 and ends blindly a short distance i^osterior to tlie genital apertures 

 (Fig.l). 



Immediately within the oral aperture is a sphincter muscle, and 

 radiating to the body-wall and endoskeletal rods previously men- 

 tioned are six strands of muscle, constituting together a dilator 

 oris. These muscles are striated ( Fig. '2 ) . 



The oesophagus is lined by a columnar epithelium, whose com- 

 ponent cells are, for the most part, completely hyaline, some, how- 

 ever, having granular cytoplasm (Fig. 16). 



The general arrangement and relative size of the various com- 

 l>artments is sufficiently evident from the diagram (Fig. 1) and 

 transverse sections (Figs. 20 to 25) ; it remains to describe the epi- 

 thelium lining it, and a peculiar digestive (?) gland secreting into 

 the second compartment. 



The anterior portion of the first compartment is lined by an 

 exceedmgly irregular epithelium, depicted in Fig. 19. The cells, of 

 extremely variable size, have a very granular cytoplasm, the granu- 

 larity being variable. The largest granules (zymogen) are found in 

 the enlarged bulbous ends of the lai'ger cells, and are apparently 

 shed by actual abstrietion, since structures precisely similar to the 



