ikedale: on invalid generic names. 173 



J. F. Kingston". The limits of the "District" wouhl rest in the 

 imagination of tlie reader. 



MoDioLAECA, Gray. 



This genus-name first appears in the Synopsis of the Contents of 

 the British Museum, 42nd ed., p. 151, 1840, where, associated with 

 Crenella, the two genera constitute the family Crenellidte. I have 

 shown in my Collation of these Synopses (these Proceedings, vol. x, 

 pp. 294-309, 1913) that here the genus-names are all absolutely 

 nomina mida. On p. 306 I noted that in the fortj'-fourth edition short 

 diagnostic remarks were added, and quoted those referring to this 

 generic name, which read " (p. 82) The Crenellce are suborbicular and 

 theModioIarice ovate elongated shells ", and added a ' ' Note : Modiolarca, 

 184U, is thus a misprint for Jlodiolaria ". 



Further investigation shows this conclusion to have been incorrect, 

 and that we have liere another instance of Gray's juggling with 

 names, as in the case of Livona. 



In Dieffenbach's Travels in Neiv Zealand, vol. ii, p. 259, 1843, Gray 

 included 



" Jlodiolarca impacta. 



Mytilus cor, Martyn, U.C., t. 77. 



Mtjt. impactus, Hermann, !Naturf., xvii, 147, t. 3, f. 5-8, xix, 183 ; 



AYood, Cat., 59, f. 40. 

 M. discors, Australis, Chemn., viii, f. 768. 

 Modiola discor, Lam., vi, p. 16. 

 Myt. lanafus, Caloiine, Cat., 43. 



Inhab. jS'ew Zealand, Dr. Solander ; Bay of Islands, Dr. Sinclair ; 

 East Cape, Dr. Dieffenbach." 



This is the first recognizable introduction of the genus-name 

 Modiolarca, and as it is associated with impacta it must fall as a 

 synonym of the earlier Jlodiolaria. It is now obvious that the name 

 was intended by Gray for the species now called Jlodiolaria, but that 

 in 1847 when he drew up his List of the Genera of Recent MoUusca 

 (Proc. Zool. Soc, 1847, p. 129 et seq.), recognizing Beck's prior 

 name, he deliberately transferred his genus-name to a different group. 



Sentimentally it grieves me to part with the genus-name Modiolarca, 

 as it will ever be associated in my memory with my discovery of its 

 existence on the mainland of New Zealand, and my personal 

 acquaintance with it and its strange habits (Trans. New Zeal. Inst., 

 vol. xl, 1907, pp. 386-7, 1908). 



As a delightful recompense, however, I found the available 

 substitute was none other than 



Gaimardia, Gould, U.S. Expl. Exped., vol. xii, p. 459, 1852. 

 The loss of Modiolarca seems more than balanced by the restoration 

 to active use of the genus-name given to honour one of the two most 

 famous shell collectors that have ever visited the shores of New 

 Zealand. It was my unfortunate lot to consign to synonymy the 

 genus-name Quoyia (these Proceedings, vol. ix, p. 259, 1911), and I 

 tried to make amends by the introduction of the genus-name Quoyula 



