MAZATLAN BIVALVES 1? 



in a position to do so. Hinge teetli, 1 in each, valve, rarely 

 seen in adult. 



Largest specimen measures long. '63, lat. 1'17, alt. '47, 



A broad flat sp. „ . „ '4, „ '68, „ '24, 



A long narrow one „ ,, "3, „ '66, „ '2, 



SmaUest „ „ -02, „ -04, „ 'OlS. 



Hah. — ^According to Forbes, Atlantic Ocean, Boreal Seas, 

 Africa, Ckina, Australia. — Canaries, Wehh Sf BertJielot, B. M. 

 Cat. Can. MoU. p. 22, no. 195.— jS"ew Zealand, Capt. Stokes, 

 B M. — S. solida : Clefts of rocks, 18 fm. St. Elena, Cuming : 

 Peru, Lima, Callao, UOrUgny, B. M. Cat. p. 58, no. 510.— 

 S. distorta. Say, Ebode Is. Jay.—S. PJioladis, Sea of Okotsk, 

 Middendorf. —M.a.zdX\&n ; in Spondylus Lamarckii, nestling in 

 crevices and burrows, also in Cbams and PateUa Mexicana, 

 very rare adult, not common jim. ; L'pool Sf Havre Coll. 

 Fossil, Crag, &c. ; very large in the pleistocene beds at Ud- 

 devalla, Sweden, B. D. D. 



Tablet 60, 6 yoimg valves.— 61, 1 valve and 6 pairs various 

 ages and shapes. — 62, 1 specimen bored into, and the valves 

 cemented open by tube of borer : also 2 fragments to shew 

 ligament. — 63, A young specimen in hole of Lithodomus cau- 

 digerus in Imperator imguis. — 64, A specimen in situ in a Yer- 

 metus, oiFback of Spondylus. 



Family PETEICOLID^. 



Genus PETEICOLA, Lam. 



« 



24. Peteicola eobusta, Sotv. 



Proc. Zool. Soc. 1834, p. 4,7.— Sow. Thes. Conch, part xv. p. 775, 

 no. 14 ; pi. cLxvi. f. 16, Vl.—MuUer, Syn. Moll. p. 229, no. 9.— 

 PMlippi in Zeit. fiir Malac. 1848, p. 163, no. 33, quasi sp. 

 nov. : . edidit Desk, in B. M. Cat. Veneridce, &c. p. 210, no. 10. 



? = P. bulbosa, Gould's plates, ms. 



The name of this sliell, which was well described by Sow. in 

 1834, was appropriated by Philipiii in his Zrd Centuiy of new 

 shells for a supposed new species ; which turns out fortimately 

 to be a small si^ecimcn of Sow.'s species, and thus confusion of 

 .'iyuouj'my is unexpectedly avoided. Deshayes has luifortu- 



