210 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



Pinnotheres in the branchial sac, four only being free from 

 parasites. The copepoda were Doropygus pulex, many, 

 males and females, and Ascidicola rosea, a few, all females, 

 and were scattered over the inner wall of the branchial 

 sac, a few being attached to the endostyle, the dorsal 

 lamina, the peripharyngeal bands, the tentacles, and even 

 in the branchial siphon. Five or six copepoda is an 

 ordinary number to find in a branchial sac, but one 

 Asciclia examined contained 15. 



Amongst many slight variations noted occurred that of 

 the tentacles shown in PI. X., fig. 1, where, besides the 

 two ordinary alternately-placed sizes, a third very much 

 smaller size of tentacle was found scattered irregularly. 

 Another specimen showed the curious abnormality of the 

 alimentary canal represented in PL X., fig. 2, where a 

 large caecum (cce.) was present, running anteriorly from 

 the highest part of the intestinal loop and parallel with the 

 rectum. Two specimens (PL X., figs. 3 and 4) showed 

 extensive deficiencies in the wall of the branchial sac. 

 Although these may be the result of former injuries from 

 which the animal has recovered, they cannot be due to very 

 recent tearing at the time of capture or death, as the edges 

 of the gaps are smooth and provided with a slight seam or 

 margin, and have no projecting or torn blood vessels. On 

 the other hand, they may be congenital deficiencies. The 

 one specimen (fig. 3) shows an J shaped space on the left 

 wall of the sac, of which the vertical limb measures 2 - 2 cm. 

 and the horizontal 1"5 cm., w T hile the breadth of the gap 

 is in most parts from 6 to 8 mm. The second (fig. 4) has 

 a gap on its left wall 12 mm. long and 6 mm. broad 

 in its middle, while on the right wall, close to 

 the dorsal lamina, there is an elliptical space measuring 

 8 mm. by 2 mm. 



Two of the specimens had the posterior end of the test 



