238 Miscellaneous. 



become much increased iu width ; and here their contents become 

 developed into a very remarkable body, which has the power of 

 extending itself beyond the orifice of the tube, and of again with- 

 drawing itself far into the interior, exactly like the hydranth or 

 polypite of a campanularian hydroid in its hydrotheca. When ex- 

 tended, it displays from around the margin of a wide terminal 

 orifice its beautiful crown of tentacles ; but when withdrawn into 

 the interior of the cup-like receptacle, the tentacles are greatly 

 contracted and thrown back into the cavity of its body. Its general 

 appearance, indeed, is very like that of a campanularian hydranth ; 

 and a careful examination is needed in order to show that it pos- 

 sesses all the essential characters, not of a hydranth, but of a me- 

 dusa. It has a circular canal surrounding the terminal orifice and 

 supporting the tentacular crown, and it has four symmetrically 

 disposed longitudinal canals extending from the circular canal 

 backwards in the walls of the body. No manubrium could be 

 detected, though this w r as carefully sought for at the point where 

 it might be expected to be found — namely, w r here the medusiform 

 zooid passes into the common coenosarc which occupies the narrower 

 portion of the tube ; neither was there any appearance of a velum, 

 nor of lithocysts or ocelli ; but these are comparatively unessential 

 modifications. 



The reproductive system is probably developed in the walls of 

 the longitudinal canals ; but in none of the specimens examined 

 was this part of the organization sufficiently mature to admit of a 

 satisfactory demonstration. 



For the little animal thus constructed I propose the name of 

 Stepluinoscyphus mirahilis. Whether it is to be regarded as para- 

 sitically connected with the sponge, or whether the two are only 

 accidentally associated, it is at present impossible to say. At all 

 events, in no instance did I find the Stephanoscyphus unaccom- 

 panied by the sponge. 



Stephanoscyphus may then be regarded as a compound hydrozoon 

 whose zooids are included in cup-like receptacles resembling the 

 hydrotheca? of the calyptoblastic hydroids ; but these zooids, instead 

 of being constructed like the hydranths of a hydroid, are formed on 

 the plan of a medusa. It has plainly very decided affinities with 

 the Hydroida, but is nevertheless removed from these by a distance 

 at least as great as that which separates from them the Sipho- 

 nophora. It thus becomes the type of a new hydrozoal order, 

 for which 1 propose the name of Thecomedtts^e. — Nature, Julv 30, 

 1874. 



Description of the Slcull of a new Species of Dolphin (Feresa 

 attenuata). By Dr. J. E. Gray, F.R.S. &c. 



The British Museum has lately received from M. Godeffroy, of 

 Hamburg, a skull of a dolphin (but, unfortunately, it is without any 

 habitat) which proves to be an unrecorded species of the genus Feresa. 



