444 MARINE INVERTEBRATES 



animal of Tellina has long, slender siphons, which are separate. 

 The gills are small, and the outer lamella or branchial fold is 

 directed dorsally. Although the foot shows evidences of a bys- 

 sogenous gland, there is no actual byssus. The shells are por- 

 celanous and translucent, equivalve, with an external ligament, 

 and at least two cardinal teeth in each valve. 



T. radiata. This species varies from three to four inches in lengtb 

 and from one and a half to one and three fourths inches in height. It is 

 highly polished, shining white, and yellowish about the umbonal region, 

 and has three wide rays of bright pink extending from the beaks to the 

 ventral margin. On account of its remarkable coloration it is called the 

 " setting-sun shell." Its surface is smooth. A common variety is of a 

 uniform creamy-white color with carnation beaks. This shell is always 

 offered for sale by the marine curio- and shell-dealers in Florida seaside 

 resorts, and at Atlantic City, Cape May, and elsewhere. 



T. alternata resembles the last in shape, being flattish and oblong, 

 but it is more pointed or angulated posteriorly. There is also a slight 

 twist in the posterior end of the shell. Its surface is decorated by nu- 

 merous impressed concentric lines. The color is nniformly white or yel- 

 lowish, with pink rays. Length two and a half to three inches ; height 

 two and a half inches. Found from Hatteras to the Gulf of Mexico, in 

 shallow, sandy stations and on beaches after storms. (Plate LXXXI.) 



T. bodegensis. The most striking species of Tellina found on the 

 west coast, and of rather northern range. It is about two inches in 

 length, creamy- white in color, and ornamented with very fine concentric 

 lines. A very characteristic feature of the genus is present in this spe- 

 cies as in the last, namely, a slight twist or bend to one side in the pos- 

 terior end of the shell. 



T. tenera. A little Tellina 

 found in New England waters, 

 which, though very small, is 

 worthy of mention on account 



Tellina tenera, showing ex- ^^ f : t P V>iiTirlsinpe> rmnn all nnr 



tended animal. ^v Tellina tenera. OI lts aDUndanCe Upon ail OUr 



beaches north of Hatteras. It 



is only about half an inch long, and slightly over one quarter of an inch 

 high. It may be distinguished by its general generic characters, its 

 iridescent surface, and its delicately marked lines of growth ; some- 

 times it is rose-tinted. Its remarkably long siphons are shown in the 

 accompanying figure. 



GENUS Macoma 



M. secta. A very pretty thin glossy shell from two to three inches in 

 length and about one fourth less in height, which occurs from Monterey 

 southward. The posterior end of the shell is contracted and slightly 

 bent ; the pallial sinus is deep. There is an external ligament. (Plate 

 LXXXI.) 



M. nnsuta. Another Californian species, with a less shining surface 

 and a very thin light-brownish epidermis. The twisting of the posterior 



