NOTKS ON SOME BRITISIt NUDIIBKANCHS. 369 



Alder and Hancock's plate, spotted with white and witli a reddish- 

 brown band about a third of the way down. The cerata are spotted 

 with opaque white and brown and have white tips, below which is often, 

 but not always a distinct reddisli-brown ring ; they are carried as 

 represented by Alder and Hancock, but there are only five or at most 

 six groups, arranged as follows : — 



1 



4 



4 



4 



4 



3 



The hepatic diverticula are not nearly as green as represented by 

 Alder and Hancock, but greyish brown with only a faint greenish tinge. 



The jaws bear a single row of small but distinct blunt denticles. 

 The radula consists of a single series of seventeen teeth, not tapering con- 

 spicuously ; there are five denticles on each side of the central cusp, 

 which is not much higher than the rest. Beaumont found the verge to 

 be armed with a colourless spine, but I was unable to discover it. 



If Cratcna and Amphorina are maintained as separate genera, it is 

 difficult to say to which this species should be referred. Beaumont 

 found that it had a single otolith and a style on the penis, characters 

 which belong to Amjyhorina ; but the cerata are not inflated, the radula 

 is short, and the denticulation of the teeth is not like that found in 

 Ampliorina . I therefore describe the animal, tliough with considerable 

 hesitation, as Cratena amoma. 



CALMA, A. & H. 



Much confusion has arisen about this genus, for later authors have not 

 paid sufficient attention to the statements made about it by Alder and 

 Hancock, and these statements, which are scattered in various parts of 

 the monograph, are not always plain if taken separately, tliough if taken 

 all together they are clear enough. Alder and Hancock described the 

 type species first in the letterpress to plate 22 (under the name 

 of Uolis gl(iucoidcs) as a very curious Eolis which will probably 

 constitute a new generic type, and pointed out the remarkable charac- 

 ters of the " gastro-hepatic vessel" and "the ovary." Tiieir language 

 about the radula in this passage is wanting in precision, but in the 

 letterpress to plate 47 {Tongves of the Eolidvla) they say that 

 the tongue is very slender, resembles a continuous band, and can only 

 be seen in profile. The figure clearly represents the tongue as I have 

 found it, a continuous chitinous ribbon in which the tcetli are fused 



