NOTES ON A COLLECTION OF CAI.IFORNIAN NUDIBRANCHS. 47 



ovate in shape (4 millim. x 3 milHm.) constricted at the base but tapering 

 suddenly to a pointed tip, though this feature is not visible in the drawing. 

 On the inside they bear a number of small prominences, at least two rows 

 of ten each, connected by ridges. The structure is not very plain but may 

 represent some form of branchia though this is not suggested by Cockerell's 

 sketch (fig. 8). 



In front of the rhinophores is an oral veil, 1-5 millim. wide at its 

 broadest part. It is undulated but shows no processes or distinct tentacular 

 prolongations. There is no trace of tentacles near the mouth. The rhino- 

 phores are stout (3 millim. x 2 millim.) and deeply but somewhat irregularly 

 perfoliate. They are much contracted but look as if they had originally 

 had a process or sharp point in front. They have no sheaths and are 

 apparently not retractile, for though there is a slight hollow at their bases it 

 looks as if they could not be withdrawn into it. The genital orifices are 

 about 3 millim. behind the frontal veil, inconspicuous and without folds. 

 The vent is at the extreme posterior end of the right side. It is very wide 

 but not very prominent. 



The central nervous system is yellowish and very distinctly granulated. 

 The eyes are large, black with a reddish lens and set on long stalks. The 

 cerebro-pleural ganglia show a very distinct division : in fact in the prepara- 

 tion the two parts are separate, but this is perhaps not natural. The pedal 

 ganglia are below them and applied to the sides of the oesophagus. 



The jaws are yellow, not denticulate, and apparently bear three 

 ridges, arising near the hinge. They seem however somewhat crumpled 

 and perhaps have been injured owing to the eversion of the buccal mass. 

 The formula of the colourless transparent radula is 22 x i. r. i. i. i. In 

 the middle of the wide naked rhachis is a small elongate central tooth (fig. 

 9) bearing a longish straight spine. With the highest power, traces of one or 

 two denticles seem visible at the base of this spine in some teeth, but they 

 are very small. The first lateral (fig. 10), which is a considerable distance 

 from the central tooth, is somewhat as in Coryphella, hamate, with a longish 

 base and 6-8 distinct denticles. The second lateral (fig. 1 1 ) has a very long 

 base and a large curved hook, blunt and not denticulate. 



The oesophagus passes under and into the liver, which is dark green, 

 and appears superficially to be a single solid mass, but on examination is 

 seen to be trilobed, one of the lobes being slightly bifid. No diverticula 

 or branches are visible, though there are holes in the surface of the liver 

 whence they might have issued. But no diverticula can be detected in the 

 papillae by either sectioning or squashing. The substance of the papillae 

 seems to be homogeneous and only slightly yellower in the centre than out- 

 side. It is certain that they do not contain a column of green substance 

 analogous to the liver. No cnidocysts could be found. Enclosed in the 

 liver is a thin, membranous, almost transparent stomach with a few internal 

 laminae. This and the intestines are full of gritty matter and many small 



