53 149 



Koh Chueii, 30 fathoms (3). 



1) Long. 172 mm., alt. 112 mm. 2) Long. 183 mm., alt. 112 mm. 



Distribution: — Gulf of Suez, Red Sea. — Amboina, Australia. 



Pinna Strangei, Hani., is undoubtedly only a form of the present species with- 

 out scales upon the ribs. L. Moklet ' records Pinna Cliemnitzi, Hani., from "the 

 islands in the Gulf of Siam;" can this be due to erroneous determination? The 

 Danish Expedition, at any rate, did not bring home any specimen of this species. 

 Ci.ESsiN, in his Monograph of the genus Pinna, in "Martini and Chemnitz, Con- 

 chylien Cabinet," figures and describes quite another species under the name of 

 P. Strangei, Hani. Pagenstecher^ records P. hystrix-forxns from the Red Sea, and 

 also forms having ribs without scales (from the same locality), which he names 



P. atropnrpnrea, Sow. 



Pinna attenuata, Reeve. 



Pinna atlenuata, Reeve, Conchol. icon., XI, Pinna, 1S58, Sp. 46. 



— — Menke, Mahtini U.Chemnitz, Conchyl. Cabin., Vlll, 1 Abtli., p. ö'J, pi. "iT, fig 1. 



— Stulcltluirii. Reeve, Conchol. icon., XI, Pinna, 1859, Sp. 64. 



— — — Martini u. Chemnitz, Conchyl. Cabin., VIII, 1 Abth., p. 74, pi. 30, fig. 2. 



Off Tung Kaben, 6 fathoms, mud mixed with sand (1). 



Long. 173 mm., alt. 51 mm. 



Distribution: — Madras, Gulf of Manaar, Gulf of Suez, Red Sea. — Moluccas, 

 Moreton Bay (Australia). 



The specimen from the Gulf of Siani bears a few scales on some of the raised, 

 longitudinal ribs; this is also found often to be the case in specimens from the 

 Red Sea.' I have given P. Stutchburyi, Reeve, as a synonym, as I cannot see any 

 difference, worthy of mention, between these two forms.' 



Pinna mutica, Reeve. 



Pinna maiica, Reeve, Conchol. icon., XI, Pinna, ISöS. Sp. 33. 



— — — Martini u. Chemnitz, Conchyl. Cabin., Vlll, 1 Abth., p. 68, pi. 2(), lig. 2. 



Koh Chuen, 30 fathoms (1). Koh Kram, 30 fathoms (1 young s|)ecimen). 



Long. 38 — 147 mm., alt. 13-63 mm. 



Distribution: — Philippines. 



Pinna madida, Reeve, P. euglypta, Hani., and P. vespertina, Reeve, show great 



resemblance to the present species, and will perhaps prove to be synonyms of P. 



mutica, Reeve. 



Pinna serra, Reeve. 



Pinna serra. Reeve, Conchol. icon . XI, 1858, Pinna, Sj). 43. 



— — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., Vlll, 1 Abth., 1891, p. (iU, pi. 28, fig. 2. 



' Journal de Conchyliologie, vol. 37, 1889, p. 161. 



- Ueber die von Kossraann am Rothen Meere gesamra. Mollusken. Lpzg. 1877, p. 30. 



' For details concerning this and the variation, etc. of P. Stutchburyi comp. Pagenstechek, 

 Ueber die von Kossmann am Rothen Meere gesamm. Mollusken. Leipz. 1877, pp. 30 — 31. 



■* Professor Ed. v. Martens says in a letter to me, that these two forms: "sind einander sehr 

 ähnlich und gehören vielleicht beide zu Einer Art." 



