162 



SHELLS. 



NATICA INTRICATA. Natica intricala, Fleming's 

 Brit., An., p. 319. Nalica intricata, Donovan's Br. Sh., 

 t. clxvii. Natica canrena, Montagu's Test. Brit., Sup. 148. 



The only British Naturalist to whom T am able to refer, 

 for information concerning the Natica intricata, is Dr. Flem- 

 ing, who in his History of British Animals gives the 

 authority of Donovan's British Shells, under the name above 

 given, and to Colonal Montagu, who terms it N. canrena; but 

 he adds, " this species has occurred only to Mr. Donovan." 

 And when I add, that Professor E. Forbes (Malacologia 

 monensis, p. 62) supposes it to be the same with TV. nitida, 

 and that it is not to be distinguished from some other foreign 

 species, it will be allowed to be of rare occurrence; and I 

 am therefore led to hope that a description of it, derived 

 from more than one example, and compared with the kindred 

 species N. glaucina of about equal size, and both of these 

 with several smaller specimens of each, will be found 

 interesting. 



The shell termed by Fleming N. intricata has too rarely 

 come within the observation of British Naturalists to have 

 received so man)' names, as the fancies or mistakes of authors 

 have affixed to the more common species. But to avoid all 

 errors in reference it is necessary to say, that under the 

 name Natica glaucina is meant that which by Pennant is 

 denominated Nerita glaucina, and it is believed, also by 

 Montagu : by Fleming Natica glaucina. Professor Edward 

 Forbes, as quoted above, terms it Nalica inonitifera, from 

 a supposition that it may be the shell so called by Lamark; 

 and the same is adopted by Macgillivray : (Molluscous 

 Animals of Aberdeen &c, p. 125.) 



In September of the present year (1844) I obtained a 

 specimen of Natica intricata, from Penzance, and this I 

 supposed to be the first I had ever seen. But in the course 

 of the same month I obtained a much larger specimen from 

 Plymouth sound; and a comparison of this pair with a fine 

 specimen of the more common N. glaucina will enable me to 

 give a measurement and description which will in some 

 measure fix the identity of the rarer species. 



The smaller specimen of N. intricata here referred to, 

 measured ten twelfths of an inch in its longest diameter; 

 but the larger, which was seventeen twelfths in its longest 

 diameter and thirteen twelfths in its shortest diameter, 

 afforded a closer comparison with N. glaucina ; my largest 

 specimen of which is sixteen by thirteen twellths in these 

 diameters. The latter, therefore is a rounder and more 

 compact shell, the greater comparative length of N. intricata 

 being obvious on inspection. They differ also in the ar- 



