134 Mr. H. J. Carter on 



be seen. Size of largest specimen, viz. that described (the 

 other, which is very small, being just the opposite in point of 

 general form), about \ inch high by 5-12ths inch in its 

 greatest diameter. 



Ohs. It is remarkable here that while the quadriradiates 

 abound on the surface and are so large as to form a character, 

 their absence is equally characteristic on the surface of the 

 cloaca. To facilitate recognition of the quadnradiate on the 

 surface it might be observed, as in the preliminary remarks, 

 that the passage of the light through the centre of the head or 

 triradiate portion invariably causes that part to present a dark 

 triangular space, whose points are in the angles of the rays ; 

 while when the triradiate is in such a position as to show a 

 dark area (that is when viewed laterally), this is quadrangular. 

 At first sight the presence of the large quadriradiate on the 

 surface causes this species to resemble the British Leuconia 

 Johnstonii ; but the peculiar form of the quadriradiate and 

 its fourth arm on the cloaca of the latter, together with 

 other minor difterences, causes it to be merely a variety. 



34. Aphroceras ascoyioides. 



Individualized and social. Specimen consisting of a group 

 of individuals growing from a contracted base. Individual 

 long, narrow, tubular, sessile, somewhat compressed, dimin- 

 ishing in size towards the free end, which is truncate, and 

 contracted towards the other, which is fixed ; without peri- 

 stome ; va)ying in size under 1^ inch long by 3-24ths inch 

 in transverse diameter, often putting forth a bud or small 

 branch towards the lower part. Colour yellowish white. 

 Surface even, glistening when dry, com])osed of a layer of 

 long, slightly curved acerates, arranged longitudinally and 

 very near together, separated only by cribriform sarcode, 

 traversed so thickly by the exserted arms of internal radiates 

 as to present a minutely hispid appearance. Pores, the holes 

 in the cribriform sarcode, opening between the long acerate 

 spicules, and in the midst of the exserted arms of the internal 

 radiates. Vent single, terminal, naked, leading into a cloacal 

 cavity which is tubular, corresponding with the shape of the 

 individual ; presenting no cloacal structure, but a number of 

 minute circular pores in direct continuation witli those of the 

 surface, in the midst of a layer of spongozoa in juxtaposition, 

 with which that remarkable granuliferous nucleated body 

 called by Hackel the " Kern" (to which I have already alluded 

 in describing Glathrina cavata, 'Annals,' 1886, vol. xvii.p. 502) 

 is plentifully mixed j supported on a skeletal structure composed 



