178 MESSRS. L. MURBACH AJfD C, SHEARER ON ^ [June 13, 



Probcscidactyla Brandt. 



1. Proboscidactyla brevicirrata Haeckel (18, p. 160). 



Synonym P . Jiavicirrata A. Agassiz. 



Specific description. — The bell is a truncated oval, 7 mm. high 

 by 6 mm. broad ; the subumbrellar cavity occupies less than half 

 this bell, leaving a clear thick mass of jelly forming the roof of 

 the dome. Agassiz has well repi'esented this in his figure in the 

 IST. A. Acaleph^ (2, fig. 280, p. 173). The velum is quite 

 narrow. The tentacles are short, and number in our largest 

 specimen 54, being half as long again as the diameter of the 

 bell. Small tentacle-bulbs bear the dark ocelli, and young 

 tentacle-buds are seen between some of the older ones. Seen 

 from the aboral side, an opaque cross marks the position of the 

 four lobes of the stomach, on which a portion of the gonads rest. 

 The lower portion of the stomach is more cylindrical, ending in 

 the tubular much-folded mouth. This sometimes appears as four 

 double folds, curved outwards and upwards. The gonads lie in 

 the interradial folds of the stomach, and pass out along the 

 unbranched portion of the radial canals. The radial canals branch 

 twice dichotomously, and then somewhat more irregularly, so that 

 there is finally a canal for each tentacle. Between the terminal 

 branches of the radial canals are blind delicate canals running in 

 centripetally from the margin of the bell, reaching halfway up. 

 These canals are on the exumbrellar surface, and do not appear to 

 be hollow in section ; the radial canals are nearer the sub- 

 umbrellar surface. Nematocysts are seen scattered in clusters 

 along these tubes at varying intei'vals, so that many masses of 

 nematocysts may be found along the course of one tube. 



Colour. — The stomach is a dirty yellow. Agassiz (2) states 

 that this Medusa is quite transparent. Whilst this is true of the 

 upper part of the bell, the thick yellow mass of the stomach 

 renders the lower portion quite opaque. Preservation in formalin 

 seems to have caused considerable shrinkage : our measurements 

 apply to preserved animals. 



Habitat. — Victoi-ia Harbour, collected by Shearer ; Pleasant 

 Beach, collected by Kincaid. 



Discussion. — Nothing was seen answering to Agassiz's (2) 

 description of the granular covering of the bell, except the patches 

 of nematocysts already mentioned scattered here and there along 

 the centripetal canals. Haeekel (18) has thrown doubt on the 

 presence of nematocysts on these canals ; they are so well marked 

 in all our examples that it seems strange he should have over- 

 looked them. 



This Medusa was fii'st found by Mertens on the coast of 

 Kamchatka. Agassiz (2) reports it from the region of Puget 

 Sound, but Haeckel considers Agassiz's species difierent from 

 that of Mertens, naming it P. brevicirrata. These names are 

 liable to give rise to some confusion. It is very doubtful if this 



