248 Mr. H. J. Carter on Deep-sea 



length of- the other (PI. XIV. fig. 32, b) ; so that this, being a 

 constant occurrence and making its appearance in the em- 

 bryonic form, must be considered a normal condition of the 

 spicule. Dr. Bowerbank's specimen was dredged up " at 

 Shetland." 



In Esperia cupressiformis there is a very minute form of 

 the same kind of tricurvate (PI. XIV. fig. 18), but with a 

 bulbous inflation at the extremity of each arm and other 

 differences which will be learnt by reference to its description. 

 I have also just found a minute sponge on the " rocks " 

 here (Budleigh-Salterton), not more than 2 lines long, con- 

 taining a similar spicule, but without bulbous ends, hairpin- 

 like. It is very minute, not being more than 2-6000ths inch 

 long, but in company with the same kind of equianchorate 

 and double form of skeleton-spicule as those in Halichondria 

 fbrcipis, though not the same species. 



All, however, are eclipsed by the beautiful form which I 

 have figured of a much stouter forcipiform spicule that came 

 from an arenaceous deposit in the neighbourhood of Colon or 

 Aspinwall, Panama, five specimens of which, having been 

 mounted, were sent to me by Mr. F. Kitton of Norwich. 

 Here the arms in all are equal in length and the extremities 

 abruptly pointed, indeed, may be termed conical ; this, to- 

 gether with the great development of the spines, points out 

 a different species from that of Halichondria forcipis, for 

 which I propose the name of Forcepia colonensis (PI. XV. 

 fig. 47). Size of specimens 19 by f-1 800th inch in its 

 greatest diameters; width of bend 2-1800ths inch, distance 

 of ends 3-1800ths inch. In Schmidt's Suberites arciger, from 

 the coast of Greenland (Atlantisch. Spongienfaun. p. 47, 

 Taf. v. fig. 6), we appear to have another example of this 

 form of spicule, in which the body is smooth and the ends, 

 which are strongly though scantily spined, so far separated 

 from each other that the spicule forms two sides of an almost 

 equilateral triangle, the distance between the free ends being 

 about 53-6000ths inch. This, too, Schmidt calls a tricurvate 

 (Bogen). 



The forceps-form of the tricurvate spicule in Halichondria 

 forcipis is therefore not confined to this sponge, or kind of 

 sponge, since it appears, as before stated, in Esperia cupressi- 

 formis, in the Budleigh-Salterton specimen, in Suberites 

 arciger (if I am right in identifying the tricurvate in Schmidt's 

 sponge with it), as well as free in this arenaceous deposit about 

 Colon. At the same time it should be remembered that this 

 spicule is subject to great variety in form, since I have lately 

 found it here (in a new species of Esperia) straight (that is, 



