CLASSIFICATION OF THE BRACHIOPODA. 



73 



middle line, but on reaching the central septum, they become perhaps free at their extre- 

 mities. The mantle adheres closely to the shell and is not seen except as a part of it. 



Fig. 21. 



Fig. 22, 



Fig. 23. 



Argiope Neapolitana 



Argiope decoUata. 



A. decoUata, with the animal. 



Obs. Having described this Genus in part 1, p. 8, and in part 2, p. 16, it will not 

 be necessary to add any further details. 



Geol. range. — The genus in the present state of our knowledge seems confined to the 

 cretaceous, tertiary, and recent periods. 



Examples .- A. decemcostata, Roemer, sp. ; A. hirundo, Hag., sp. ; A. decoUata, Chem., 

 sp. ; A. cuneata, Risso, sp. ; A. Neapolitana, Scacchi, sp. ; A. cistellula, S. Wood, sp. ; &c. 



Sub^Family— STRINGOCEPHALID^. 



Antmal unknown, attached during the greatest part of its existence by means of a 

 muscular peduncle : labial appendages supported by a largely developed calcified process 

 or loop : a mesial septum -. small in the dorsal, large in the ventral valve. Cardinal pro- 

 cess extending to the ventral septum : shell structure widely punctated. 



Obs. The peculiar assemblage of remarkable characters possessed by Stringocephalus, 

 has rendered the exact place the section should occupy somewhat difficult to determine. 

 The presence of a loop and punctated structure connects the genus with the Terebratulidce, 

 but it cannot be properly admitted into that family, on account of its acute beak, 

 position of the foramen, deltidium and largely developed septa, which last-named 

 characters belong more particularly to the Bhynchonellida ; it will therefore be preferable, 

 at least for the present, to follow Professor King in keeping the section distinct, by placing 

 it in a small sub-family, close to the Terebratulidce. 



Genus — Stringocephalus, Bef ranee, 1827.^ 



Tyjje— S. BuBTiNi, Bef. Int., PI. VII, figs. 95—98. 



Terebratula (part), V. Buck, &c. 



Strigocephalus, Def., and of the generality of Authors. 



' Die. d'Hist. Nat., vol. li, p. 102, pi. Ixxv, fig. 1, la, 1827. 



* Most authors write the name Strigocephalus, but the proper spelling is Stringocephalus. 



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