50 THE NAUTILUS. 



As Mr. Lea afterwards received several large cumingii he was 

 of course acquainted with its appearance, and hence his placing the 

 two shells together. But the tenacity with which Mr. Lea "hung 

 on " to his names is an old story, and accounts for his placing them 

 as allied but distinct species, in his classification. 



However, even though synonymous with each other, it is probable 

 that gigas has not precedence, since it was published by Sowerby 

 long after Lea's U. cumingii. Moreover, U- gigas Sowerby is prob- 

 ably not the undescribed U. gigas of Swainson. 



An adult specimen of the species under discussion is illustrated on 

 Plate VI, from the writer's collection. It is 209 mm. long, and was 

 received from China. 



The remains of the high wing, and the broad biangulated posterior, 

 the purplish color inside, and the wrinkled umbones amply distinguish 

 U. gigas (cumingii) from either of the shells with which it was 

 united by Mr. Simpson and Mr. Call. 



Anodon moretonianus Sowerby. 



On page 925 of the synopsis Mr. Simpson makes a variety 

 moretonianus Sowerby of Glabaris trapesialis Lamarck. The 

 variety being shown in Sowerby, Conchologia Iconica xvii, 1867, 

 PI. IX, fig. 20. This appears to be a singular error. The shell 

 figured not only is not trapesialis Lk., but is nothing like it. It is 

 more than probable that Mr. Simpson in haste, made a " lapsus 

 pennse " and really intended to make a variety susannce Gray; for 

 this shell is close to, if not identical with trapesialis, and is figured 

 on the same plate to which we are referred. But be this as it may, 

 the Anodon moretonianus of Sowerby (as of Lea) is nothing like 

 Glabaris trapesialis Lam. 



Unio plicatulus Lea. 



A singular lapsus seems to have been made on page 353 when the 

 genus Ctenodesma is described and the type assigned is the Unio 

 borneensis Issel, better known perhaps as the U. plicatulus of Lea. 

 But there can be but little doubt that this shell (i. e., the V. 

 plicatulus Lea.) is not a member of the Ctenodesma at all, but un- 

 questionably belongs to the next described genus Rectidens. 



