Miscellaneous. 443 



apparatus. The spermatophore breaks up and becomes disaggre- 

 gated ; the spermatozoids are then set at liberty, and spread in the 

 copulatory branch, the copulatorj vesicle, and especially the ovi- 

 gerous channel, where at this moment, and at this moment only, we 

 find them in great quantities and full of life. By the action of the 

 vibratile cilia which line the inner wall of the ovigerous channel, 

 the spermatozoids go to meet the ova ; and it is in the commence- 

 ment of this channel that fecundation appears to be effected. 



During the preludes of copulation the two individuals project 

 their dart, which usually traverses through and through the walls 

 of the visceral cavity, where it may be found long afterwards among 

 the viscera, slightly altered. The dart, contrary to the opinion ex- 

 pressed by a malacologist, when once detached, is speedily repro- 

 duced. Within a few hours of the copulation its rudiments may 

 be perceived ; and a few days suffice for its complete reproduction. 

 We may therefore, in some cases, from the degree of development of 

 this calcareous style, judge approximately of the time that has 

 elapsed since the last sexual intercourse. — Comptes Rendus, Oct. 30, 

 1871, p. 1059. 



Oti the Persistence of Caryophyllia cylindracea, Reuss, a Cretaceous 

 Coral, in the Coral-fauna of the Deep Sea. By P. Martin Duncan, 

 M.B. Lond., F.R.S., F.G.S., Prof, of Geology in King's Coll. Lond. 

 The author first referred to the synonyms and geological distribu- 

 tion of Caryophyllia cylindracea, Reuss, which has hitherto been 

 regarded as ijeculiar to the White Chalk, and as necessarily an ex- 

 tinct form, inasmuch as it belonged to a group possessing only four 

 cycles of septa in six systems, one of the systems being generally 

 incomplete. The distribution of the CaryoplujlUcti of this group in 

 the Gault and the Upper Chalk, the Miocene, and the Pliocene was 

 noticed, and also that of the species with the incomplete cycle. The 

 falsity of this generalization was shown to be proved by the results 

 of deep-sea dredging off the Havannah, under Count Pourtales, and 

 off the Iberian peninsula under Dr. Carpenter and Mr. Gwyn Jef- 

 freys. The former dredged iip Caryophyllia formosa with four 

 complete cycles ; and the latter obtained, from depths between 690 

 and 1090 fathoms, a group of forms with four complete and incom- 

 plete cycles. This group had a Cretaceous facies ; one of the forms 

 could not be differentiated from Caryophyllia cylindracea, Reuss ; 

 and as a species of the genus Bathycyathus was found at the same 

 time, this facies was rendered more striking. The representation of 

 the extinct genera Trochosmilia, Parasmilia, Synhelia, and Diblasus 

 by the recent Amphihelice, Paracyathi, and Caryophyllice was 

 noticed ; and it was considered that as the Cretaceous forms throve 

 under the same external conditions, some of them only being per- 

 sistent, there must be some law which determines the life-diu'ation 

 of species like that which restricts the years of the individual. It 

 was shown that deep-sea conditions must have pi'evailed within the 

 limits of the diffusion of the ova of coral polj^^s somewhere on the 

 Atlantic area ever since the Cretaceous period.— Proc. Geol. Sac. 

 June 7, 1871. 



