140 Mr. P. S. Abraliaiu on some Genera 



above a dorsally expanded, fimbriate, longitudinal crest, the 

 margin of which is tuberculate or denticulate. Upon the 

 sides of the body are a few minute rugose tubercles, similar 

 to those upon the lateral processes ; they are more numerous 

 and larger behind the last pair of processes near the base of the 

 tail. The general colour in the spirit specimen is whitish and 

 semitransparent, irregularly spotted with small, brown, unequal 

 blotches and speckles, especially close and dark around the 

 branchiaj, behind the dorsal tentacles, on the upper border of 

 the supracapital veil, and on the sides of the tail. They are 

 small, close, and numerous on tlie sides of the foot. The bases 

 of the lateral processes are spotted with brown posteriorly, the 

 rest of the process being minutely dotted with opaque white. 

 The large rounded apices of the last pair are opaque yellowish. 

 The laminte of the dorsal tentacles are brown posteriorly or 

 below, and shade off into brownish white above ; the pedicles 

 are semitransparent and white. The branchige are closely 

 speckled with dark brown, except on the margins. The 

 extreme edge of tlie oral tentacle is unmarked ; then comes a 

 row of minute, dark, close speckles, within which tlie surface is 

 sparingly dotted. The lower surface of the foot is yellowish 

 and free from spots. 



Dimensions (in spirit) — length 35 millims., breadth 12, 

 height 14. 



Hah. New South Wales. 



P. ncevatus differs from all the other described species of the 

 genus in not having the branchiae on the centre of the back. 

 It resembles P. ocellatus alone in having the lateral dorsal 

 processes unbranched, and P. {mperialis in having sessile 

 marginal appendages to the frontal veil. 



Ceratosoma, Adams & Reeve. 



Body elongate, prismatic, smooth or nearly so, ending in a 

 bluntly pointed tail, the dorsal surface passing into a protu- 

 berance behind the branchiae; mantle obsolete; dorsal tentacles 

 laminate, generally retractile within cavities. Branchiae plu- 

 mose, with the roots more or less coherent, in front of and 

 partially around the tubular anus, retractile within a smoothly 

 margined cavity. Mouth subterminal, with a small deep pit 

 at each side. Pedal surface long and linear, extending to end 

 of tail, without free border, but with the edges contractile 

 across the median groove. Odontophore broad, with numerous 

 rows of simple spines, none of which are central ; a spinous 

 buccal collar. 



