ON MOLLUSCA OF THE WEST COAST OF NORTH AMERICA. 203 



form of the common species : P. 360. Cardium Californiense, Califor- 



also found at Mazatlan. nia. M. Z. pi. 4/. = C. Nut- 



P. 358. Petricola Cordieri, California. tallii, Conr. : not C. Califor- 



= Venus lamellifera, Coiir. M. nianum, Conr. 



Z. pi. 18. Siphonaria scutellum, " He Cha- 

 Petricola arcuata, California. M, tam." ? Galapagos. 



Z. pi. 19. Purpura Freycinetii, Kamtschat- 

 Petricola cylindracea, California. ka. M. Z. pi. 26. Much more 



(Probably P. arcuata, var.) M. like P. lapillus than Midden- 



Z. pi. 20. dorff's figures. 



P. 359. Venerupis gigantea, California. Murex macropterus. 



—Saxidomus Nuttalli, Conr. Helix Dupetithouarsi, Monterey. 



Venerupis Petiti, California. M. Z. pi. 30, as " rsii." 



= Tapes diversa, Sow. jun. P. 361. Velutina Mulleri, Kamtschatka. 



Anomia macrochisma, Kamt- Turbo digitatus, Acapulco. 



schatka. M. Z. pi. 34. =.Pla- = Uvanilla unguis, Wood. M. 



cunanomia m., Gray. Z. pi. 36. 



Cypricardia Duperreyi, Califor- Natica Recluziana, California. 



nia. M.Z.pl.27. M. Z. pi. 3/. 



Modiola cultellus, Kamtschatka. Natica ianthostoma, Kam- 

 P. 360. Cardium Loperow^'i, California*. tschatka. 



M. Z. pi. 48. Natica sanguinolenta. 



To the above must probably be added Purpura emarginata, p. 360, M. Z. 

 pi. 25, described by Deshayes as from New Zealand, but quoted in Jay's Cat. 

 no. 8972, = P.Conradi, Nutt. MS., from California; and from the same 

 locality in Mus. Cuming, on the authority of Mr. Hartweg. Many of these 

 shells were figured in the following year in Guerin's Magasin de Zoologie, 

 between plates 14 and 48, of which references are given above. In the same 

 works are described, Lucina cristata, Reel. Rev. Cuv. 1842, p. 270, Guer. 

 Mag. pi. 60, found " sur le banc de Campeche" by M. J. Cosmao, Commander 

 of the Naval Station of Pvlexico, = Tellina Burnetii Brod. & Sow. : and Lucina 

 corrugata, Desh., Guer. Mag. pi. 82, as from California, which Mr. Cuming 

 found himself at Singapore. 



The official description of the shells of the Venus, however, was intrusted 

 to M. Valenciennes, under whose auspices was published " Voyage autour du 

 Monde sur la Venus, pendant les annees 1836-39, par M. du Petit Thouars. 

 Paris, 1846." Of this work plates only have been seen, of which the following 

 are species connected with the West N. American coast. 



Plate. Fig. 



1 2. Helix vincta, Val. (California, live.) 



24 4, 4a. Plwlas rostrata, Val. Almost certainly the young of one of the 



following species. 



24 1, 1 a, b. Penitella Conradi, Val. (Pholadidea, with long, inflated cup, 

 without divisions.) 



24 2. Peniiclla xilophaga, Val. (Pholadidea, with long, narrow cup.) 



24 3, 3a, b, c. Penitella tubigera, Val. Probably a variety of the last; the tube 

 being simply the lining of the old cavity, as in P. calva. 



24 7 a, b. Bornia luticola, Val. (Closely approaches Chironia Laperousii, 



Desh.) 



24 8, Sa. Saxicava clava, Val. (Probably S. legumen, Desh.) 



16 2, 2a. Venus per dix, Val. ? = Chione neglecta, Sow., represented with- 



out pallial sinus. 



16 3,3 a. Venus pcctunculoides,Y&\. = Tapes histrionica, Sow. 



2 2, 2a. Trochus amictus, Val. = Uvanilla unguis, Mawe. sat Turbo digi- 



tatus, Desh. 



* Described from a single shell which appears worn. It has much the aspect of a Tellina, 

 with concentric ridges and no internal crenations; but is figured without pallial sinus. 



