nNrniimit.f: — I!i;f:inal[,. oOf) 



111 1831 Kliroiil)t're;''' coiif lihiiti'd observiitioiis on flic jirobalilc means 

 of I'espiiiition, wliicli later was to become a question of coiiKicierable ai'pfii- 

 nient ; and in 1882 Andouin and Milne Kdwards'^ recorded some habits 

 and observations on Onchidium celficiaii, noticed by Cuvier, but not 

 described by him. In this year too Deshayes'-'' records his opinion that 

 the species already described could not be safely g'iven a systematic position 

 until further research had been conducted. 



In liis " Kipfures of Molluscous Animals," by Mrs. (rray, Ciray''' has 

 ofiven his consideration to the family and tabulates a list of four orynera 

 and eighteen species ; and he introduces the new genus ihicliidelhi, to 

 which he allots ten species hitherto known as ihirliiditou, though the 

 specification of this genus is confined to a single phrase " back without 

 radiating processes". 



The year 1852 brings an addition of live new species as described by 

 Couthouy and Gould'". 



Forbes and Hanley'*^ in 185o record intei-esting observations for the 

 time on Onchldhnu ceUicniii, and perliaps correctly desire to credit the 

 authority of the species to Couch and not to Cuvier ; to these observations 

 are appended some anatomical notes communicated to the authors by 

 Hancock. 



Milne Edwards'", who had in 18;^)2 given his opinions on the habits 

 and organisation of Our/iidliiiii relticnnt. with Audouin, withdi'aws these 

 opinions in his " LeQons sur la Physiologic at I'Anatomie de I'Homme et 

 des Animaux " and agi'ees with the previously recorded opinions of 

 Ehrenberg. 



Keferstein-'^^' in 1805 published some valuable notes on the genitalia of 

 the Onchidiida>, and while these observations are held by Joyeux-Laffuie 

 to be of little importance, and probably incorrect, it is worthy of notice 

 that Keferstein's observations would cause tlie Onchidiidii?, to be considered 

 among the Opisthobrauchiata. 



In 1869 Stoliczka^i re-established the faulty description of the geno- 

 type Onchidium typjia', and in addition to describing some new species he 

 gives some observations on their habits. 



In 1871 Vaillant-- published his anatomical research on Ihicliidimn 

 celtlcnm and Tasle-'' and Recluz-^ also made additions to the knowledge of 



' •"' Ehrenberg — Symbolse Physicic sen Icones et descriptiones animalium everte- 

 bratorum, decas prima, 1831. 



'•' Audouin and Milne Edwards — Kecherches pour servir a rhistoire uaturelle du 

 littoral de la France, i., 1832, p. 118. 



'•'' Deshayes — Hist. nat. des vers., ii., 1832, p. 663. 



I'i Gray- Vol. iv., 1850, p. 117. 



'"Couthouy and Gould — Wilkes U.S. Explor. Exped., xiii., Moll., 1852, pp. 

 290-293. 



'•^ Forbes and Hanley— British Mollusca, iv., 1853. p. 3, pi. FFF, fig. 6. 



>9 Milne Edwards — Legons sur la physiologie et I'anatoniie de rhoiume at des 

 animaux, 1857-81. 



-'" Kefersteiu— Zeits. wiss. Zool., xv., 1865, pp. 86-93, pi. vi., figs. 14, 15. 



-1 Stoliczka — Journ. Asiat. Soc. Bengal, xxxviii., pt. 2, No. 2, 1869, p. 99 et seq. 



■" Vaillant — Compte Rendu, Ixxiii., 1871, pp. 1172-1174. 



2:! Taslo — Journ. de Conch., xix., 1871, p. 368. 



-■• Recluz— Act. Soc. Linn. Bord., xxvii. (Mel. Malac), 1871, pp. 59-62, 



