OF CONCHOLOGY. 163 



Observations. — Cannot well be compared with any of our 

 species. Its exterior cannot be called attractive; its rich, 

 golden-brown interior is its chief characteristic. Resembles 

 A nod. leprosa, Villa, of Europe, in form, but is never so 

 roughly decorticate, is a little more inflated, and the nacre of 

 our species is incomparably richer and more brilliant. The 

 posterior slope has two obscurely raised angles of a wavy 

 character, and also marked by a dark-brown line on the 

 summit of each. Its crowded marks of growth are distin- 

 guished by similarly colored lines, which are, however, 

 narrower. 



Anodox glandulosa, Anthony. — t. 16, f. 3. 



Description. — Shell elliptical, inequilateral, thin; epidermis 

 yellowish-olive, with faint green rays over the whole disk; 

 more numerous, and crowded on the posterior slope, which is 

 consequently decidedly green; beaks but slightly raised, 

 rugose at tip ; marks of growth free, distant, and well 

 defined; ligament long, thin, brown; nacre silvery white, and 

 remarkably iridescent. 



Habitat. — Michigan. 



My Cabinet. Cabinet of Hugh Cuming, London. Mus. 

 Comp. Zoology, Cambridge, Mass. Cabinet of George W. 

 Tryon, Jr. 



Observations. — This species may at once be recognized by 

 its peculiar form, — like an elongated gland. When young it 

 is beautifully and broadly rayed on the posterior half of the 

 shell, whilst the anterior portion is so finely and delicately 

 rayed, that it presents hardly more than an uniformly greenish- 

 yellow surface. 



Resembles in some degree Anodon imbecillis, Say, but is less 

 inflated, less uniformly green, and the color is never so intense 

 as in that species. The beaks of Anodon glandulosa are ele- 

 vated and wrinkled, while those of Anodon imbecillis are flat 

 and smooth. The marks of growth in this species are very 

 conspicuous, and, with the broad green rays, give the shell a 

 remarkably pleasing look. The posterior end is somewhat bi- 

 angular, with a third raised line nearer the ligament, indicated 

 by a darker color. 



AxoDON lEiSAXS, Anthony. — t. 16, f. 2. 



Description — Shell smooth, elliptical, rounded before, and 

 obscurely angulated behind ; valves very thin and semi- 

 transparent; epidermis olivaceous, with capillary greea rays 

 from the beaks to the basal margin, intersected by very 

 conspicuous darker lines of growth, about seven or eight of 



