Polyzoa of the Adriatic. 259 



expanding upwards ; aperture sloping inwards and extending 

 almost across tlie cell, seta long and very slender. Ooecium 

 simple, rounded above, somewhat contracted towards the 

 orifice ; surface smooth and shining, punctured, the oral arch 

 marginate. 



There can be little doubt, I think, that this is the Acamar- 

 chis BertJwlletii of Savigny's work, a species which has not 

 jet been identified. Busk, in his 13rit. ^lus. Cat., placed it 

 doubtfully amongst the synonyms of his Scrupocellaria 

 diadema ; but in his ' Challenger ' Report the latter is referred 

 to Crisia ciliata^ Audouin. There is a complete agreement 

 between Savigny's figure and the species from the Adriatic, 

 extending to the minuter details. 



There is also, I think, the greatest probability that Heller's 

 Scrupocellaria capreolus was founded on specimens of the 

 present form, though both his diagnosis and figure are too 

 slight to give us the information we require for a certain 

 identification. 



It is pretty evident that the bi- or trifurcate spine of his 

 description is really the scutain ; this is sufficiently indicated 

 by its position • and if so there is a complete agreement in 

 tliis element of structure between his species and S. Berthol- 

 letii. The characters of the aperture and the disposition of 

 the spines in S. capreolus also point to the identity of the 

 two forms. The spine on the inner margin a short distance 

 above the scutum is especially characteristic. The lateral 

 aviculariuni is small and an inconspicuous feature, as in S. 

 Bertholletii. On the other hand, the ooecium of the latter is 

 not raitriforra, as that of S. capreolus is represented to be in 

 the figure, but both are punctured ; the front avicularia are 

 apparently wanting in Heller's species. 



On the whole there seems to be ground for believing in 

 the identity of the two forms. S. Bertholletii is common 

 amongst the material which has come under my notice, and 

 would probably not be overlooked by one who was investi- 

 gating on the spot the fauna of the Adriatic. I have met with 

 no other form which could have suggested Prof. Heller's 

 description or figures. 



There is a curious irregularity in the development of the 

 scutum in the present species. Very often it is absent alto- 

 gether or present oidy in very rudimentary condition on a few 

 cells. Commonly it occurs as a bifurcate spine-like process, 

 and only iu rare instances, so far as my experience goes, 

 does it present the appearance shown in the figure (PL IX. 

 fig. 1). As Savigny's figures represent it as universally a 

 niere bifurcate spine, the feeble develoj)meut of this appendage 



