NUDIBRANCHIATA OF THE L.M.B.C. DISTRICT. 145 



cerata which are short and stout in form. The hepatic 

 caeca under a low powder of the microscope are seen to be 

 irregularly speckled with green and black pigment, while 

 at the apex the cnidophorous sac forms a large opaque 

 yellowish mass. This apical colouring is not superficial as 

 in the case of Corypliella landsfmrc/i, C. rnji/iranchialis, and 

 other species, but is apparently in the wall of the sac itself. 

 There is, how^ever, a little opaque white sprinkled down 

 the anterior surfaces of the cerata. One of the larger 

 cerata was found to be bifurcated at its tip, and provided 

 with two distinct cnidophorous sacs. Curiously enough 

 the single specimen from Puffin Island, which we recorded 

 last year, showed exactly the same abnormality.* 



The cnidophorous sac (PI. IX. fig. 12) is flask shaped, 

 and communicates with the hepatic caecum by a very short 

 tube. Several masses of gland cells (^/.) are placed around 

 the junction. 



The table on the following page shows the distribution of 

 the species of Kudibranchs recorded up to now in the four 

 regions of our district which have been sufficiently investi- 

 gated. The first column includes Hilbre Island, w^hile the 

 third takes in the Menai Straits and the coast of Anglesey : 

 we separate Puffin Island from the preceding region 

 merely because it may be convenient for those working 

 at the Biological Station to know what species have been 

 found on the shore. Fifteen species have now been ob- 

 tained at Puffin Island. 



* Proe. Biol. Soc, Liverpool, vol. iii., p. 234, 



