Vol. 50.] THE COAL-FORMATION OF NOVA SCOTIA. 439 



Synonxmt of Naiadites. 



1840. Naidea, Swainson, for Unio-\ike molluscs. 



1845. Naidea, Buckman, ' Geology of Cheltenham,' Rhsetic and Stonesfield 



plants. 

 1845. Naiadita, Brodie, Fossil Plants (in ' Fossil Insects '). 

 1850. Naiadita, Buckman, adopted in Quart. Journ. Geol. Soc. vol. vi. p. 415. 



1853. Dawson figured several Molluscs from Nova Scotia resembling Modiola 



and Unio, Quart. Journ. Geol. Soc. vol. x. (1854) p. 39. 



1854. Naiadites, Morris, for Naidea aud Naiadita, in his ' Catalogue of British 



Fossils.' 



1855. Dawson again figured one of these molluscs as a Modiola, 'Acadian 



Geology,' 1st ed. p. 148. 



1860. Dawson gave a short description of the shells and referred to the above 



figure, provisionally naming it Naiadites. He described also several 

 species ; the first and type species being Naiadites carbonarius. Sup- 

 plement to 1st ed. ' Acadian Geology,' p. 43. 



1861. Salter gave the name of Anthracomya to certain British Coal-measure 



molluscs with full descriptions and figures, Mem. Geol. Surv., ' Iron 

 Ores of Great Britain,' pt. iii. p. 229. 



1862. Salter speaks of three species of Naiadites he had received from Dr. 



Dawson, namely Naiadites elongatus, N. carbonarius, and N. Icevis. 

 The first and last of these he refers to Anthracomya, and for the other, 

 N. carbonarius, Dawson's type, he proposes the name " Anthracoptera 

 for these triangular shells." 



If the name of ' Naiadites ' can be retained for any of these 

 molluscs it must be for this type-species N. carbonarius, for which 

 Salter erroneously proposed the generic name of Anthracoptera, Quart. 

 Journ. Geol. Soc. vol. xix. (1863) p. 80. 



Note. — Wheelton Hind, 1893 (see below), says that the form figured 

 by Salter, Quart. Journ. Geol. Soc. vol. xix. p. 79, fig. 3, as Anthracoptera 

 carbonaria is not the same as Dawson's type, ' Acadian Geology,' 1st 

 edit. p. 148, and Quart. Journ. Geol. Soc. vol. x. p. 39. 

 1868 & 1878. Dawson gives figures and descriptions of these Nova Scotian shells 

 and partially adopts Salter's names as sub-genera for some of the 

 species, thus: Naiadites (Anthracoptera) carbonaria, Naiadites (Anthra- 

 comya) elongata, Naiadites (Anthracoptera) lisvis ; but speaks against 

 Salter's idea of the marine nature of these shells (as quoted above, 

 p. 436), 'Acadian Geology,' 2nd & 3rd edit. p. 202 et sequ. 



1893. Wheelton Hind adopts Salter's two genera Anthracomya and Anthra- 



coptera, for the British species, but says that the specimen from 

 Nova Scotia figured by Salter as Anthracoptera carbonaria is not the 

 same as Dawson's Naiadites carbonarius ; the latter, Hind says, is 

 an Anthracomya, Quart. Journ. Geol. Soc. vol. xlix. (1893) p. 249. 



1894. Wheelton Hind in the MS. of the present paper proposed to adopt 



Naiadites for Anthracomya, and to retain the name of Anthracoptera 

 for the type-species of Naiadites. He now acknowledges that Salter's 

 Anthracoptera carbonaria is the same as Dawson's Naiadites carbo- 

 narius. The genus Naiadites, therefore, will have to be used and 

 Anthracoptera discarded. The British forms referred to the latter 

 genus, in the author's 1893 paper, will now be called Naiadites. 



I must admit the error of which I am convicted by Sir William 

 Dawson — namely, that I confounded Naiadites Icevis and Estheria 

 Dawsoni — the more so as the fault was due to carelessness in com- 

 paring the numbers of quoted pages. 



I am not able to state that any of the species submitted to me 

 are the same as British forms, therefore the specific names must 

 still remain, though, if at any time in the future more perfect 

 specimens are obtainable, it may be quite possible to do so. 



