OF CONCHOLOdY. 343 



Lottia gigantea, Gray. 



Gray ms. in Brit. Mus., Sowerby, Gen. f. 1 ; Reeve, Conch. 

 Syst.f. 1, (copied.) 



=A. scutum, nonnull. ms. (vide Mazatlan Catalogue, ji. 208): 

 non Eschscholtz, nee D'Orbigny. 



= \_Tecturella~] grandis, Gray, Smithsonian Institute Chech 

 List, No. 176; British Association Bejjort, 1861, p. 137. 



L. t. magna, crassiore, planata, expansa; textura soepius 

 spongiosa; nucleo minore, corneo, nigrofusco, ancyliformi, 

 vertice mamillato, subelevato; dein elongata, postice grisea, 

 undulata ; t. adolescente verrucosa, radiis obscuris, antice haud 

 verrucosis; t. adulta plus minusve lata; plus minusve radiata, 

 seu verrucosa; apice plus minusve a margine remota; parte 

 antica seu baud projiciente, sen circiter quinta totius longitu- 

 dinis; parte postica plus minusve elevata, convexa: extus, ut 

 in "Acmasa pelta" picta, albido-grisea, fusco-olivaceo copiose 

 irregulariter strigata: intus, plerumque testa testudinaria, mar- 

 gine lato, nigro; spectro definito, fusco, seu rarius albido; cica- 

 trice musculari fortiore, interdum purpureo seu violaceo tincta. 



Sp. normalis, A, long. 2*6, lat 2"05, alt. 7. 

 " varians, B, " 2"95, " 2"35, " 8. 

 Ex apice ad marg. ant. sp. A *45 ) Apicis alt. A *6. 



" B -05 j " B -35. 



Habitat. — California Inferior. 



This shell, by far the largest in the family, has been long 

 known in collections, and comes to us from various quarters 

 of the world. The United States Exploring Expedition spe- 

 cimens were duly labeled "Valparaiso." It is only known to 

 live, however, in Middle and Lower California. The peculiar- 

 ity of the mantle-fringe was first pointed out to me by Dr. 

 Cooper in 1860, when preparing the Smithsonian Institute 

 Check Lists. To distinguish it, I proposed the name T^Cw- 

 rella, in order to preserve the remembrance of Tectum, Milne 

 Edwards, which falls as a synonym of Acmsea. I was not 

 aware that "Dr. Stimpson had previously employed it in his 

 •'Invertebrata of Grand Marian." I then proposed the name 

 Lecania, under which I may have distributed duplicates; but 

 on the eve of publication by Dr. Alcock (from whose notes I 

 have copied the above diagnosis of the animal) and myself, 

 I was fortunate enough to obtain the loan of that very rare 

 but most excellent work "Sowerby's Genera," which was the 

 original of Mr. Reeve's well-known "Conchologia Systematica." 

 Here our very shell appears, excellently figured, as the first 

 species of Gray's "Lottia" and with his ms. name gigantea. 



