622 Appendix to Part II. 



DES'TALiril G1GANTBUM. — PL II. fig. 1. 



Dentalium testa tereti, rectiusculd, sufcis longitudinalibus numerosis, 

 interstitiis rotundati-s : long.?>"2) lat. Oo, poll. 



This species appears occasionally to grow to a very large size, 

 for one fragment that is one inch and a third in length, is half an 

 inch in width at its smaller extremity, and six-tenths of an inch at 

 its larger ; while in its thickest part the shell itself is 013 of an 



inch thick. 



Navidad, Chile. 



Dextalitjm: sulcostjm. — PL II. fig. 2. 



Dentalium testa tereti, rectiusculd, costellis longitudinalibus 

 elevatiusculis, subdistantibus 14, interstitiis planulatis. 



The proportions cannot be given ; for there is only one frag- 

 ment, which has been broken and the two pieces conferrnminated 

 by the sandstone in which it occurs. 



Navidad, Chile. 



DEXTALiinr iiAjrs. — PL II. fig. 3. 



Dentalium testa tereti, rectiusculd, costis longitudinalibus 24, alternis 

 majoribus, interstitiis rotundatis. 



The proportions of this species cannot be given, because there 

 are only some fragments : it appears to be one of the larger 

 species of the genus, probably reaching the dimensions of 

 D. sexangulare of Deshayes, tab. 3, fig. 4. It differs from that 

 species in the circumstance of its never having only six angles ; 

 a ad it differs from D. elephant inum of Deshayes (which I have 

 elsewhere proved not to be the D. elephantinum of Linnaeus) in 

 being less rapidly attenuated, and in being straighter. 



Huafo Island, coast of Chile. 



BaLAXUS V ASIANS. — PI. II. figs. 4, 5, 6. 



Balanus testa polymorphd, valvis plerumque Icsvibus, nonnunquam 

 radiatim obtusd costatis, apicibus subacuminatis ; valvd basali 

 modb concavd, modb cyathiformi, basi acuminata. 



This is a very remarkable as well as a very variable species. 

 Its parietal valves are sometimes smooth, only showing the lines 

 of growth, and-^onietinies covered with obtuse radiating ribs ; and 



