244 Mr. W. King on some Shells and other Invertebrate Forms 



strongly-marked varieties of this well-known shell, apparently 

 consequent on the depth at which they live : thus the variety 

 found in from fifteen to twenty fathoms water is thick and elon- 

 gated, and the one procured from the greatest depths is thin, 

 short and tumid. On contrasting these two varieties, many would 

 pronounce them to be distinct species ; but they are completely 

 blended by a form which lives at an intermediate depth — about 

 forty fathoms. The shallow-water variety, as it may be called, 

 resembles the specimens figured in Capt. T. Brown's ' British 

 Conchology/ 2nd ed. pi. 6. f. 8 ; Pennant's ' British Zoology/ 

 vol. iv. pi. 78 ; and Donovan's 'British Shells/ vol. ii. pi. 31. My 

 largest specimen is 6 j inches in length and 3^ in width, and has 

 nine whorls. 



I do not know of any published figure that represents the deep- 

 water variety ; perhaps the best idea of its form will be conceived 

 from the following measurement of a median size specimen, 

 which is 5^ inches long and 3| wide, and has eight whorls ; 

 to which I may add, as general in the- variety, that the whorls are 

 extremely ventricose, that the siphon or canal is strongly twisted, 

 and that when old the outer lip is very much reflected. 



The largest specimen I have got, and which is now in the 

 cabinet of Mr. J. Alder, is 7 inches in length and 5 in breadth, 

 and has nine whorls. 



The only figure I can find to illustrate the intermediate form 

 is in Midler's ' Zoologica Danica/ pi. 118. fig. 1. My largest 

 specimen measures 7 inches by 3f, and has eight whorls. I 

 ) have specimens approximating closely to Fusus carinatus. 



Fusus norvegicus = Strombus norvegicus, Chemnitz. 



The only British locality hitherto published for this species is the 

 Yorkshire coast. I have procured it both from the coast of North- 

 umberland and of Durham, where it lives in deep water. Although 

 figured in the great work of Chemnitz, it is surprising that so 

 few conchologists, continental or British, were aware of the ex- 

 istence of this shell until Dr. Turton announced it as having been 

 found by Mr. Bean of Scarborough ; a reduced copy of Chemnitz's 

 figure is given in Wood's ' Index Testaceologicus.' 



Fusus norvegicus differs decidedly from Fusus antiquus, with 

 which it has occasionally been confounded : the canal is shorter 

 and wider ; the apical or nucleate whorls are considerably larger, 

 being as large as in some of the mammillated Volutes ; and the 

 inner lip is much more expanded, being spread over the ventral 

 convexity of the body- whorl considerably beyond its median line ; 

 further, it is much smoother externally, is more highly polished 

 internally, and has a shorter spire ; nor has it the siphonal ridge 

 of Fusus antiquus. . 



