PLATE IV. 



The basement membrane and the nephridial apparatus are on this plate indicated by a red tint. 



Kg. 1. Carinina //rata, n. gen. et sp. A longitudinal section through the body- wall at the point where 

 the terminal duct of the nephridia (Nc) pierces it. LTI/and ec, muscular layers (see PL III. 

 figs. 3, 4); Abasement membrane; E, cellular integument, with superficial and deeper 

 gland-cells, separated by a layer of closely contiguous nuclei that belong to extremely 

 elongated cells, placed perpendicularly to the surface. 



Fig 2. Carinina grata, n. gen. et sp. Section through a region where the nephridial canal (Nc) is still 

 enclosed in the blood-space (Bs) in which a distinct cellular coating is observable, and 

 which is separated from the intestinal caeca (Je) by the inner circular muscular layer (<■/., 

 Cm, figs. 5, 6); LM, the outer longitudinal muscular layer. 



Fig. 3. Carinina grata, n. gen. et sp. A longitudinal section through the (esophagus (Oe). Je, its ciliated 

 epithelium directly applied upon the muscular layers Cm, LM, and ec (see PI. III. fig. 3); 

 PSW, the proboscidian sheath-wall, very thin, with the oesophageal epithelium below 

 and its own nuclei above it. This fibrous wall is confluent superiorly with the layer of 

 circular muscles Cm (cf. PI. II. figs. 5, 9, 10). 



Fig. 4. Carinina //rata, n. gen. et sp. Section through the spongy and canalicular part of the uephridium 

 (Nsp), and the region where it communicates with the principal nephridial duct Nc ; Bs, Je, 

 LM, and Cm, as in the preceding figures. 



Figs. 5, 6. Carinina grata, n. gen. et sp. Transverse sections of the same system. The nephridia lie in 

 the blood-spaces (Bs) which have their own cellular coating, and are partly enclosed in the 

 circular muscular layer Cm. Ps and Oe indicate the respective situation of proboscidian 

 sheath and oesophagus in relation to the nephridia ; Nsp and Nc as in fig. 4. 



Fig. 7. Carinina grata, n. gen. et pp. A portion of the oesophageal epithelium under higher power. Je, 

 the granular epithelium cells ; e, the cuticula with the cilia. 



