158 J. E. S. MOORR. 



hinder chamber of a small stomach (PI. 14, fig. 4, ce.). In 

 the anterior chamber of this organ (fig. 4, ant. ch.) there 

 is lodged a well-developed crystalline style, represented in 

 fig. 4, c. st. The intestine passes out of the left side of 

 the posterior stomachic chamber much in the same manner as 

 iu Ty phobia. It takes the course re[)resented in fig. 4, int. 

 Towards the rectal extremity of the intestiue there is a large, 

 round, glandular lump (figs. 4 and 9, R. g.), very similar at 

 first sight to that connected with the oviducts in the female 

 Littorina. 



The liver is large, and opens by two very small hepatic 

 ducts on to the base of the posterior stomachic chamber (fig. 

 6, h. d.). 



The kidney surrounds the heart, and extends posteriorly to 

 that organ. It opens by a minute aperture, represented in 

 PI. 14, fig. 4, R., at the extreme upper end of the mantle cavity. 



The heart has tiie normal tsenioglossate characters. It lies 

 in a large pericardial cavity (PI. 14, fig. 4), and consists of — 



1, A thin-walled auricle in direct connection with the pul- 

 monary vein. 



2, A thick-walled ventricle which opens by a valvular aper- 

 ture into — 



3, An aortic trunk, from which the anterior and posterior 

 aortse proceed forward and backwards (fig. 4). 



The gill is large and somewhat peculiar (PI. 14, figs. 2, 14). It 

 occupies an elongated oval space upon the inner mantle wall, 

 and consists of numerous strong, broad, triangular gill leaves, 

 the projecting apices of which occupy the median line of the 

 structure. The apex of each leaf is prolonged into a filiform 

 process, which gives the curious appearance to the gill repre- 

 sented in figs. 2, 14. 



These filaments do not project quite straight, but are more or 

 less inclined to the rectal (left) side of the gill. On this same 

 side, each gill leaf below the median process is slightly pig- 

 mented, the whole left side of the ctenidium appearing con- 

 sequently dark in comparison with the other. 



The osphradium is long, and lies at the bottom of a groove 



