34 Mr, H. J. Carter on the 



Hob. Growing plentifully on the fronds of a foliaceous coral- 

 line (Udotea, sp.). 



Loc. S.W. coast of Australia. 



Obs, This little specimen, which I am pretty sure was sent 

 from Freeniantle to the late Dr. Bowerbank by Mr. G. Clifton, 

 is contained in a small flat pill-box bearing no other label than a 

 note of interrogation. It will therefore hereafter be found among 

 the existing Calcisponges in the British Museum, to which 

 collection I have already added several specimens. The 

 peculiar form of the large triradiate is characteristic of the 

 species ; and the solidity of the vermiculo-reticulation, which 

 is not hollow like that of the contorted tube of Clathrina, 

 Gray, = Grantia clatkrus, Schmidt, although very much like 

 it in external appearance, characterizes the genus ; while the 

 latter resembles the appearance of ZittePs fossil Calcispongise 

 generally, and the former the speculation of his genus Sestro- 

 stomella. Following Hackel's arrangement of the Calci- 

 spongias (No. 2, zweiter Band, p. vi) it belongs to his second 

 family, viz. Leucones, and is thus closely allied to his genus 

 Leucetta, in which the spicules are all triradiate ; but as he 

 mentions no instance of a u solid vermiculo-reticulation " we 

 must view this species as the type of a new genus, and hence 

 I have called it Leucetta clathrata, where, curiously enough, it 

 will be located close to his Leucetta pandora and Leucandrapul- 

 vinar (No. 2, zweiter Band, pp. 127 and 166 respectively), 

 both of which come from the west and south coasts of Australia, 

 and possess, as before mentioned, the same kind of pitchfork-* 

 like spicules discovered in Sestrostomella from the Cretaceous 

 at Vaclies Noires, near Havre, by Dr. Hinde, and confirmed 

 by myself in the specimen from the Jura, kindly sent me some 

 time since by Prof. Zittel. The specimens of Leucetta 

 clathrata which I have, although numerous, are all small ; 

 but there is no reason why much larger ones may not exist, 

 if not be found hereafter. 



Peotosycon, Zittel, 





Although there can be little doubt from Quenstedt's repre- 

 sentations (No. 7, Taf. 131. figs. 24-27) and the preparation 

 which Prof. Zittel kindly sent me, that his Protosycon punc- 

 tata was one of Hiickel's Sycones, notwithstanding Zittel's 

 want of success in displaying through thin slices the u tri- 

 and quadriradiate spicules M of which it seems to have been 

 composed (No. 8, vol. iv. p. 135), the preparation kindly set 

 before me by Dr. Hinde shows a distinct triradiate in the 

 interspaces, which would not have been there had it not come 



