108 DE. T. DAVIDSON OX EECENT BRACHIOPODA. 



Journal of Conch, vol. vi. p. 130, 1870, says that " The [Smithsonian] collection includes 

 a specimen from New South Wales (coll. Angas), sent under the ahove name \_M. triincatct]. 

 The shell and apophyses presented no constant difference from Mediterranean specimens. 

 The animal was in a perfect state of preservation in both, and I noticed the following 

 differences, of which only a much larger series would be sufficient to establish the constancy. 

 The central spiral lobe of the brachia, prominent in the European species, seemed to be 

 nearly wanting in the Australian shell. The fringes in the former were nearly twice as 

 long, the individual filaments much more slender, and five or sis times as numerous 

 as in the latter." 



Megerlia truncata, var. monstruosa, Scacchi. (Plate XIX. figs. 21, 22 «.) 



Terehratula monstruosa, Scacclii, Osserv. Zool. no. 2, p. 17, 1838, aud Cat. Coiichyl. Regui Neapolitani, 

 p. 8, 1836. 



Terebrutula monstruosa, Costa, Fauna del Regno di Napoli, p. 43, pi. ix. figs. 4, 5, 1851. 

 Megerlia truiicata, var. monstruosa, Monterosato, Poche note sulla Conch. Med. p. 4, 1875. 



When describing this shell, Scacchi observes that he suspects it might be a malforma- 

 tion of Terehratula truncata, a view reciprocated by Costa and by several other malaco- 

 logists, and it is very probable that they are correct in their expression of opinion. Having 

 had a number of s])ecimens through my hands presenting the same peculiarities, I have 

 preferred to retain for it the varietal name of monstruosa. In shape it is either circular 

 or transversely oval, and usually smaller than Megerlia truncata proper. The dorsal 

 valve is much flattened, and occasionally even somewhat concave and marked with ruts 

 and irregularities dvie to the olyect upon which it lay closely impressed. There generally 

 exists at the umbo a semicircular aperture or foramen, somewhat similar to that oiFlati/dla, 

 which affords passage, in part, to the short thick peduncle. The ventral valve is evenly 

 convex ; beak very short, with its extremity sometimes i^artly overlying the semicircular 

 aperture in the umbo of the dorsal valve ; foramen semicircular, completing that in the 

 dorsal valve. Surface of ventral valve faintly marked by fine radiating raised lines or 

 I'iblets, that of the dorsal valve with concentric lines. In the interior of the dorsal valve 

 the loop is exactly similar to that of the typical Megerlia truncata. Colour yellowish. 

 Length lines, l)readtli 6, depth 2| lines. 



Sab. Dredged alive near the Island of Corsica (Scacchi) ; also in the Bay of Naples. 



0/js. Were it not for the loop many specimens of this variety or malformation might be 

 taken for JPlatydice. 



Section B. 



62. Megerlia sangtjixea, Chemnitz, sp. (Plate XX. figs. 1-8.) 



Anomia sanx/vinca, Chemnitz, Neues syst. Conch. -Cabinet, vol. viii. p. 9G, pi. 78. fig. 706, 1785. 



Anomia sanguinolenta, Gmelin, ed. Linne's Syst. Nat. p. 3347, 1788; Dillwyn, Cat. of Kecent Shells, 

 p. 293, 1817 (not of Solandcr). 



Terehratula sangulnea, Kiister, Nov. ed. Chemnitz's Conch.-Cab. p. 33, pi. ii. figs. 9, 10, 1843. 



Terebrutula cruenta, E. Donovan (not of Dillwyn), The Naturalist's Repository, vol. ii. pi. Ivi. fig. 1^ 

 1824 (according to Donovan tliis is the Anomia cruenta of Solandcr, MS.). 



Terehratula sanguinolenta, Blainville, Diet, des Sci. Nat. vol. liii. p. 142, 1828. 



