THE ANATOMY OF ONOHOLAIMUS VULGARIS, BAST. lo9 



terminal portion. Its lumen is narrow, but this is due to the 

 thickness of the walls, as the diameter over all measures 

 "306 mm. The epithelium is the thickest layer; it is 

 columnar, and shows a remarkable iutra-cellular structure. 

 The protoplasm is differentiated into two layers, an outer 

 which stains with ha^matoxylin, and an inner which stains 

 with eosin. The former projects into the body of the cell in 

 a fingerlike process which surrounds the nucleus. 



The muscular layer is well developed, and consists, as usual, 

 of circular fibres. Muscular trabeculte pass from the body- 

 wall in the neighbourhood of the lateral lines, and converge 

 toward the midvcutral line; they are attached to the outer 

 surface of the ductus. 



The ductus opens into the cloaca. This is formed by an 

 invagination of epidermis, the wall consisting of cuticle, and 

 a protoplasmic layer continuous on the one hand with the 

 epithelium of the ductus and on the other with the epidermis 

 (subcuticular). 



The spiculjB are attached to the dorsal wall of the cloacii, 

 and pierce this wall to project through the external aperture. 



ascaris capsulaeia (kud. ?). 



Excretory Gland. 



In almost every cod numerous nematode embryos are to be 

 found encysted under the peritoneum. They occur in largest 

 numbers on the surface of the liver and among the pyloric 

 caeca, but are also common in the mesentery. They certainly 

 belong to an Ascaris, but to what species I am unable to say. 

 As usual with Nematode embryos, they occur coiled up like 

 a watch spring and surrounded by a capsule of badly-formed 

 fibrous tissue. They measure 22 to 28 mm. in length. The 

 head is blunt, with three papillae — one dorsal, two subventral — 

 around the triangular mouth. The body tapers more gradually 

 toward the head than toward the tail. There are no lateral 

 membranes. The anus is subterminal. There is no diverticulum 



