No. 3.] MONTGOMERY — 3IEN0BRANCHUS MACULATUS. 161 



forming- tlie branchial apertures, placed obliquely ou eacli side of 

 the neck, the anterior aperture being almost double as lari;e as 

 the posterior, the former permitting the current of water to flow 

 out between the first and second gills, and tlie latter between the 

 second and third gills. During sleep, the gills, so active and red 

 in the waking condition, become sluggish in movement and ])ale 

 in colour ; indeed so marked is the difference in the action and 

 colour of these external respiratory organs when awake and 

 asleep, tluit one would, at first sight of a sleeping Jlenobranchus. 

 suppose it to be dead. 



The trunk is cylindrical and thick, being usually five or six 

 inches in circumference. The tail does not become absorbed 

 and disapi^ear in the full-grown animal as it does in frogs and 

 toads, but remains during its whole life ; it is compressed o 

 flattened from side to side, forming a strong, vertical, aucipita 

 swimming organ, similar to the tail of a fish, from which, how 

 ever, it difters in being destitute of spines, and in tapering con 

 siderably so as to become lanceolate. 



Neither dermal nor epidermic plates, scales, or warty excres- 

 cences are ever developed in this creature ; on the contrary, the 

 surface ot" the body is quite smooth, soft, and more or less moist 

 and slippery, owing to a thick greyish gelatinous secretion of the 

 skin, which probably assists its movements over stones, tfcc, on 

 the bed of the stream. On removing this coating of light-grey 

 slimy matter, the upper surface and sides of the whole animal 

 are seen to be of a dark brownish-grey colour, beautifully speckled 

 or mottled with distinct large dark purple spots for the most part 

 circular in shape. The inferior surface of the body is much 

 lighter in colour than the superior surface, being of a greyish- 

 white tinged with yellow, and also sometimes dotted with little 

 purplish spots. 



On dissection of a Menohraiiclius^ the flesh is found to be very 

 white and inviting to the palate. Notwithstanding the intense 

 disgust with which most fishermen and many other persons look 

 upon it, there is no reason for supposing its flesh less savoury 

 than that of its near relative, the Axolotl. which forms such a 

 delicacy on the table of the Mexican. 



As regards its internal anatomy, it may be observed that the 

 alimentary tract consists principally of a mouth, gullet, stomach, 

 and intestine terminating in a cloaca through which pass the 

 generative products, urinary and fivcal matters. The mouth is 

 Vol. IX. I, Xo. ;.. 



