DALL: MOLLUSCA AND BRACHIOPODA. 229 



Indo Pacific, Moluccas, New Zealand. This at first sight looks very different 

 from the simple jiodom, but there are intermediate phases. 



G. 1. A. navicula Solander, Portland Cat., 1786, p. 44, no. 1055; after Rumphius, 

 Amboin. Kariteitk., pi, 18, fig. i; + A. nitida Lamarck, An. s. Vert., 1822, 

 7, p. 653 (syii. excl.) ; + A. oweni Adams and Reeve, Zool. Voy. Samarang, 

 Moll., 1850, p. 4, pi. 3, figs. la-Id; + A. kochiana Banker, Zeitschr. Mai., 

 May, 18.52, p. 49; Novit. Concli., Moll. Marina, 1858, p. 29, pi. 9, figs. 7, 8; 

 + A. polka Conrad, Journ. Acad. Nat. Sci. Phila., 1854, 2d ser., 2, p. 333, 

 pi. 34, fig. 4. Antilles, South Atlantic, Indo Pacific region. 



Even this polished species will show traces of granulation between the ribs iu 

 some specimens. Lamarck's synonyms include the auriculate form, but in his 

 diagnosis he mentions that his shell is not auriculate. 



G. 2. A. hians Solander, Portland Cat., 1786, p. 44, no. 1055 ; after Rumphius, Am- 

 boin. Rariteitk., pi. 18, fig. B ; + .i4. rjondola et hians Dillwyn, Rec. SlielU, 

 1817, 1, pp. 334, 335; + A. rarkostata Lead), Phil. Trans., 1817, p. 296, 

 pi. 11, fiJe main villa, Diet. Sci. Nat., 1820,43, p. 213;+ ^. hians Adams and 

 Reeve, Zool. Voy. Samarang, Moll., 1850, p. 4, pi. 3, figs 2a-2c ; + .^-l. crassi- 

 costa Blainville, op. cit. (young shell), p. 218. Antilles, South Atlantic, Indo 

 Pacific region. 



H. A. boettgeri Maltzan, Journ. de Conchy!., 1881, 29, p. 163, pi. 9, fig. 7 ; Smith 

 Ann. Mag. N. Hist., 1887, 4tli ser., 20, p. 409, pi. 17, figs. 1-6. Indo Pacific 

 region, China Seas, Chagus Islands, Mauritius, Australia. 



A small, closely rolled, inauriculate brown species, quite distinct in character. 



I. I. A. fragilis Parkinson, Proc. Boston Soc. N. Hist, Aug., 1856, 5, p. 387. 

 Locality unknown. 



After a careful examination of the description of this uufigured species, I am 

 inclined to believe it based on an abnormal specimen. 



I. 2. A. geniculata Gould, Wilkes Exploring Expedition, Moll, and shells, 1862, 

 p. 470, pi. 45, figs. 685 a-c ; Otia Conch., 18G2, p. 231. Rio Janeiro. 



This name is based on the animal of an Argonaut taken without the shell, and 

 fully figured in the report. 



1.3. A. rufa Owen, name only, Trans. Zool. Soc. Lond., 1836,2, p. 114; Gray 

 Cat. Moll. Brit. Mus., Ceph., 1849, p. 34. South Pacific. 



The only description of this alleged species is comprised in the five words 

 " animal and shell thick, red," in Gray's catalogue. 



I. 4. A. conradi Parkinson, op. cit., 1856, p. 386. " New Nantucket," Pacific 

 Ocean. 



The description of this small and uufigured shell reads as if it might relate to a 

 variety or mutation of A. dispar Courad. 



