193 



NOTES AND MEMORANDA. 



On the Occurrence of the Nudibranch Hancockia at Plymouth. — I am 



glad to be able to record a second English specimen of this inte- 

 resting form. It was dredged, apparently on Delesseria, in Plymouth 

 Sound, about halfway between Drake's Island and the west end of 

 the Breakwater, on August 20th, 1891. 



Mr. A. R. Hunt, the original discoverer of Hancockia, dredged a 

 single example in Tor Bay in August, 1877. This was described 

 by Mr. Gosse under the name Hancockia eudactylota (Annals and 

 Mag. of Nat. Hist,, Ser. 4, vol. xx, 1877). 



In January, 1885, four specimens, representing two closely allied 

 forms, were taken near Naples, and described by Prof. Trinchese 

 (Ricerche Anatomiche sul Genere Goria, 1886). He defined the 

 genus Goria, apparently in ignorance of Gosse's paper, including 

 his forms under two species, G. rubra and G. viridis. 



The Plymouth specimen is about a quarter of an inch in length 

 when extended. This is only half the length of Mr. Hunt's speci- 

 men and of Prof. Trinchese' s Goria rubra. 



It is of a dark claret colour, very similar to that of the Delesseria 

 on which it lived. 



The epidermis of the upper surface, seen by reflected light, is of 

 -a delicate bluish-green hue, as in Hancockia eudactylota (Gosse, loc. 

 cit., p. 317). 



There are four pairs of pleuropodial processes, with a rudiment of 

 a fifth on the left side. 



In its other characters, this specimen is apparently intermediate 

 between H. eudactylota and Goria rubra. 



In the number of processes of the oral veil (four on each side), 

 in the form of the rhinophoral sheaths, and in the absence of the 

 white spots which Trinchese has described, it agrees with Hancockia 

 and differs from Goria rubra. 



In the absence of rudimentary oral processes described by Gosse 

 between the well-developed ones, in the presence of a more or less 

 circular pigment patch at the base of the pleuropodial expansions, 

 :and especially in the form of the latter, it agrees with Goria rubra 

 .and differs from Hancockia. 



