Miscellaneous. 235 



has a series of rounded oscules, that are small near the margin and 

 gradually increase in size as they approach the centre, where the 

 oscules become united into two very large oblong rather sinuous 

 holes. The outer surface of this sponge exhibits a quantity of small 

 circular holes interspersed among the tubercles which bear the bunches 

 of spicules. 



The other sponge I have named Laharia hemisphcerlca. It is 

 hemispherical, about 2 inches in diameter, and rather more than 1 

 inch high, with a rather smooth outer surface and a rather deep 

 regular concavity on the upper surface, which seems formed of 

 interlacing spicules, leaving considerable spaces between them. 

 The outer surface and its margin are scattered with distant, but 

 rather regulai'lj' placed, cylindrical perforations, from the centre of 

 which axe emitted tufts of elongated filiform sjjicules, diverging in 

 all directions from the surface of the sponge. The middle of the 

 underside deeply concave, with a well-defined edge, from which is 

 emitted a very large tuft of very numerous crowded spicules, form- 

 ing a kind of brush, each filament when perfect ending in three 

 short recurved spines. 



Mr. Carter will give a further accoimt of these sponges, with 

 descriptions of the spicules of which they are formed, in his account 

 of the sponges in the British Museum. 



On the " Capreolas " of Zonites algirus. By E. DtrBREinx. 



In our anatomical and historical investigation of the generative 

 apparatus of the Helices, we have noticed the presence of a sperma- 

 tophore in Zonites algirus, and described the mpreolus of that species, 

 which had not been indicated by any malacologist. 



This body, 2G millims. in length and 1 millim. in breadth at its 

 most inflated portion, is of a tubular form, diminishing in size on 

 both sides from its inferior third. It is a complete canal, furnished 

 with numerous spiral channels. A transverse section made about 

 its middle has the aspect of a cogged wheel furnished with from 

 twelve to fourteen little teeth. Its superior extremity terminates in 

 a tube with a capillary aperture, where the lamella) disappear ; whilst 

 the other, where they are more distinct, is shorter and presents a 

 wider orifice. It is covered with an albuminoid membrane. 



AVhen the introduction of the capreolus is completed, its inferior 

 extremity, curving into the arc of a circle, inserts itself for three, 

 four, or five millimetres into the neck of the oviduct, which, in this 

 species, is destitute of a transverse muscle. This extremity is 

 enveloped by a whitish viscous matter, which escapes from the 

 interior of the spcrmatophore, and contains an infinity of sperma- 

 tozoids. The issue of these from the interior of this appendage is 

 due to the action of the muscular membrane of the copulatory canal. 



A part of the inferior deferent duct is destined to the production 

 of the capreolus. This duct, which measures 50 millims. in extent, 

 lias not the same volume throughout its length. Fi'om its point of 

 junction with the deferent channel for a, distance of til millims. its 

 diameter is g or at most 4 millim., whilst in the second half of its 



