Mr. A. Hancock on the Animal of Myochanna anomioides. 287 



tish Museum), has not, as yet, elicited a reply. In October 1849 

 Capt. Button communicated to me his description of the animal 

 of his sinistrorse discovery, D. Huttoni, Pfr., from Mussoorie 

 (not Muporee as printed in the Monograph), or rather from a 

 lower elevation at Jerreepanee. In this species also it appears 

 that an operculum was not observed. Can it be possible that 

 the animals of this genus have a general habit of casting off 

 their opercula ? I can only account by some such supposition 

 for not seeing it among the hundreds which I have seen or taken 

 alive, and for its escaping several examinations of the animal, 

 made with a view to description, and to fixing its position with 

 reference to the anomaly of the form among the Carychiadce, 

 unless the appendage be concealed in the fleshy part of the foot. 



Malvern, February 17, 1863. 



XXVII. — On the Animal o/Myochama anomioides. 

 By Albany Hancock, Esq. 



'' [With a Plate.] 



The animal of Myochama anomioides is at present only imper- 

 fectly known. I am, therefore, fortunate in po.ssessing an indi- 

 vidual well preserved in spirits. I owe this advantage to John 

 Wickham Flower, Esq., — the same gentleman to whom I am in- 

 debted for the specimen of Chamostrea albida which was recently 

 described in the ' Annals.' 



The mantle-lobes of the animal now before us are very unequal, 

 as might be inferred from the form of the shell, the right or 

 attached valve of which is small and flat, the left large and much 

 inflated, particularly towards the umbo, which is excessively de- 

 veloped. The mantle is delicate and pellucid, revealing to some 

 extent, through its substance, the various organs ; it is entirely 

 closed with the exception of the siphonal orifices, the pedal open- 

 ing, and a fourth minute aperture similar to that described in 

 Chamostrea. On looking down upon the large or left lobe, the 

 ovary (PI. XI. fig. \p) is seen through the membrane to occupy 

 the umbonal region, and below it the body or visceral mass and 

 gill can be partially observed. On each side the adductor 

 muscles are conspicuous; they are not large, the posterior {q) 

 being irregularly i-ounded, the anterior (/•) somewhat elongated 

 and arched outwardly. The posterior extremity of the animal is 

 slightly truncated, and here the margins of the mantle separate 

 and form a shallow recess (fig. 3), within which are situated the 



