1 1 4 PALAEONTOLOGY. 



healed during life, are preserved in the British Museum, 

 and in that of the London College of Surgeons* In all 

 perfect Belemnites, the " alveolus " is occupied by a " phragmo- 

 cone " (tig. 34, p) 9 with tender nacreous walls and septa, ter- 

 minating in a minute globular apex, and perforated by a 

 ventral siphuncle (fig. 34, i, s). The last chamber is rarely 

 preserved, and appears to have thinned off into a mere horn}^ 

 sheath, with sometimes two pearly bands like knife-blades on 

 the dorsal side. It must have been sufficiently capacious to 

 contain all the viscera. The ink-bag has been very rarely 

 found, and is even smaller than in the last genus, as if in 

 relation to the more greatly developed shell. 



The Conoteuthis (fig. 34, 3) of the Gault has an oblique 

 phragmacone, with a very thin shell, and seems to have been 

 attached to a slender style, like the funnel-shaped appendix 

 of the gladius in the recent sagittated Calamary. 



Mr. Dana has described, under the name Helicerus Fugi- 

 ensis, a belemnitoid fossil from the " slate" rock of Cape Horn. 

 It is half an inch in diameter, has a thick fibrous guard, and the 

 slender phragmacone terminates in a fusiform spiral nucleus.! 



Subjoined is a table of the extinct genera of the mollus- 

 cous province : — 



Brachiopoda. — Trigonosemus, Lyra, Magas, Ehynchora, Zel- 

 lania, Stringocephalus, Meganteris ; Spirifera, Cyrtia, 

 Suessia, Athyris, Merista, Eetzia, LTicites ; Camaro- 

 phoria, Porambonites, Pentamerus, Atrypa, Anoplo- 

 theca ; Orthis Orthisina Strophomena, Koninckia, 

 Davidsonia, Calceola ; Producta, Chonetes, Aulosteges, 

 Strophalosia ; Trematis, Siphonotreta ; Obolus. 



* See, especially, the specimen of Belemnites dbbreviatxis, from the great 

 oolite of Garsington, described and presented by the author. (Cat. of Fossils, 

 4to, 1856, No. 22, p. 7.) 



f For the drawings and most of the facts, or their verification, relating to 

 invertebrate fossils, the writer is indebted to his experienced colleague in charge 

 of that department of the British Museum, Mr. S. P. Woodward, F.G.S. 



