266 PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



and also in Gibhula Richardi, Payr., the latter author attributing the 

 notches to the Cirnpede Alcippe. 



Buccinum undatum has been seen with a new canal formed at an 

 angle to the old one,' and a specimen of Fulgiir canaliculatum has been 

 recorded by Johnson & Pilsbry ^ in which the basal canal was twisted 

 to one side. 



Pterocera varies occasionally in the number of labial digitations, 

 Willey' noticing a specimen of P. limhis which has an extra inter- 

 calated digitation; this note is of some interest with reference to the 

 origin of species, since he identifies this extra digitation with one of 

 those of P. millepeda, L. Variation in the number has also been seen 

 in P. delicatula, Nevill. 



Again, the presence or absence of the umbilicus is not constant. 

 There occurs in Mauritius and the Seychelles a race of Achatma 

 fuUca, Eer., in which the umbilicus is open. Mr. Pilsbry* states: 

 " I am disposed to think the pathologic condition may be due to 

 a disease of the left lobe of the mantle, possibly owing to some 

 specific parasite of A. fulicay 



Many species having spiral sculpture may be deprived of it by 

 injury to the mantle ; occasionally, again, species not normally carinate 

 become so, the occurrence having been observed in Helix, Placostylus, 

 Limncea, Buccinum, Rissoa, etc. 



The variation of CyprcBa seems to deserve special notice. It will be 

 a familiar fact to those who have studied the group, that there are 

 found in New Caledonia,^ mainly off the Island of Nou, deformations 

 of most of the species belonging to that fauna ; these forms are 

 elongate, beaked, and generally marked by melanism. Their coral 

 habitat or a malady of the animal have been suggested, but the 

 matter is at present an unsolved mystery. Cyprcea is also liable to be 

 marked by obtuse spiral ridges on the back ; or the spire, which 

 normally in the adult shell is flat, may be produced so as to give the 

 specimen the form of Marginella. Some specimens have been seen 

 with a curious protuberance on the back ; this is due to a Balanus 

 ha\'ing attached itself to the shell, the animal having then covered it 

 with a deposit of shelly matter. 



Of Haliotis tuherculata, L., three or four specimens have been 

 recorded^ in which the usual row of perforations is absent; and 

 a specimen of Saliotis Cracherodii has been found, measuring nearly 

 five inches in length, without any trace of perforations or indentations. 

 On the other hand, Mr. Smith '' has given an account of a specimen of 

 Saliotis, now in the British Museum, which was furnished with two 



' Levett: Zoologist, ser. ui, vol. viii, p. 490. 

 ■^ Nautilus, vol. ix, p. 25. 



* Proc. Linu. Soc. N.S, Wales, vol. xxi, p. 110. 

 ■* Man. Conch,, ser. ii, vol. xvii, p. 58. 



* Of. Dautzenberg: Journ. Conchyl., vol. li, p. 291. 



•5 Jeffreys: Brit. Conch., vol. iii, p. 281. Smith: Conchologist, vol. ii, p. 75. 

 Marquand: Journ. Conch., vol. xi, p. 48. Kelsey: Nautilus, vol. xviii, p. 67. 

 ' Ann. Nat. Hist., ser. vi, vol. i, p. 419. 



