188 DE. T. DAVIDSON ON EECENT BRACHIOPODA. 



torn in all the specimens ; but I tliink there can be little doubt that they are as represented 

 in the sketch — one end being attached to the dorsal valve close to the outer border of the 

 divaricators, the other most probably to the anterior process of the ventral valve; but I 

 could not satisfactorily determine this ; the fibres of this extremity, however, are firmly 

 united to the inner layer of the occlusors. The brachial muscle, bm, has both the 

 extremities attached to the same valve (the dorsal), the anterior end to the cardinal 

 process, the dorsal close to the outer margin of the occlusors, with which it blends its 

 fibres ; the arms are fixed to those muscles, which perhaps may be named brachial : 

 mm. is a flat thin membranous muscle binding the dorsal extremities, to which, according 

 to Woodward, the cardinal muscle is attached. The ovarian impressions have some 

 resemblance to the uniform scars in the Trodiiciklce, but they take their origin from 

 behind the occlusor muscles ; I have little doubt that they are ovarian, they can also, 

 I believe, be traced in both valves " *. 



TJncertaisi Species. 

 102. Crania Pourtalesii, Ball. (Plate XXVII. figs. 12, 12 a.) 



Crania Pourtak's'ii, Dall, Bull. Mus. Comp. Zool. Harvard, vol. iii. p. 35, 1871. 



Dr. Dall states, loc. cit. p. 35, that " the few specimens of Crania dredged by the United 

 States Coast Survey Expedition (off the Sambos, Florida, in 116 fathoms, and off the 

 Sand Key in 105 fathoms f) offer some apparently constant differences from C. anomala. 

 They are somewhat distorted, very transverse, and have obscure indications of radiating 

 rugosities. The shells are smaller than C. anomala, have a strong concentric foliation 

 caused by the imbrication of the lines of growth. The colour is much the same as in 

 anomxila ; one white sjDccimen with a few radiating brown lines M'as dredged on a stone 

 in 126 fathoms, off Sand Key, by Mr. de Pourtales. The interior of the lower valve was 

 of a green colour. The posterior muscular impressions are smaller and closer together 

 than in C. anomala. It is very possible, however, a strongly marked variety of that 

 species ; but in case the collection of a larger number of specimens sliould prove its dis- 

 tinctness I would propose for it the name of C. JPoiirtalesii, Dall." 



Obs. Never having seen this shell, I reproduce verbatim Dr. Dall's description of it. 



10.3. Crania turbinata. Poll, sp. (Plate XXVII. figs. 14-23, Plate XXVIII. figs. 1, 1 a.) 



Anoinia turbinata, Poli, Test, utriusque Sicilise, ii. p. 18'J, tab. 30. fig. 15, 1795 : Criopus fimbriatus 

 (animal), Criopoderma tnrhinatum (shell). 

 Pateltu kermes, Humplicy and Da Costa, Nat. Hist, of Shells, p. 7, pi. i. fig. 10, 1770. 

 Anomia cranioluris (part.), Gmelin, Liuu. S^st. Nat. ed. xiii. vol. iv. p. 3340, 1788. 

 Anomia turbinata (part.), Dillwyu, Cat. of lleceut Shells, p. 286, 1817. 



Crania personata, J31aiuville, Diet. Sci. Nat. vol. xi. p. 312, pi. 304, fig. 2, Cat. xv. 1818 (uot Lamarck) . 

 Crania ringens, lloeuiughaus, Beitr. Mouogr. Crania, p. 3, fig. 2, 1828. 

 Crania rustruta, lloeuiughaus, Beitr. Mouogr. Crania, p. 3, fig. 3, 1828. 



* [A series of remarkable observatious on the living animals of Crania and Discina were recorded by M. L. Joubin. 

 at the Arago zoological station, Banyuls-sur-iler, in the years 1884, 1885, and 1880. A brief abstract of his impor- 

 tant memoir, ' llecherches sur lAuatomie dcs lirachiojjodes luarticiiles,' is appended to this monograph. — A. C.j 



t Crania rourtah-sii has also been dredged oft tSt. Vincent, West Indies, in 88 fathoms (DaU, Dull. Mus. Comp. 

 Zool. Harvard, vol. xii. p. 205, 1880). 



