37. MESOl'lUON. 187 



operculum very indistinctly emarginate ; interopcrculum w ithout 

 knob. Greenish olive, with ohliciuc streaks above the lateral line, 

 and some shining golden longitudinal bands on the sides. No lateral 

 blotch, nor a spot in the axil. 

 Caribbean Sea ; Coast of Brazil. 



a. Fine specimen. West Indies. From the Haslar Collection, — 



Head above with small roimd violet spots. 



b. Half-grown. Puerto CabeUo. Purchased of Mr. Brandt. 



c. d. Adult : skins. Jamaica. From Dr. Parnell's Collection. 



e, f. Half-grown : skins. Jamaica. From Dr. Parnell's Collection. 



g. Half-grown : skin. Jamaica. Purchased of Mr. Cuming. 



li. Skin : not good state. Trinidad. Presented by J. B. Richard- 

 son, Esq. 



l-n. Half-grown : skin. West Indies. Purchased of Mr. Scrivener. 



0. Skeleton. From the Collection of the Zoological Society. 



jp. Half-grown. From the Haslar Collection. — Spotted like speci- 

 men a. 



Skeleton. — The skeleton of this species deviates more from those of 

 M. uninotatus and (/riseus than these species from each other. The 

 maxiUaiy bone gradually A^-idens from the base to its extremity, and 

 has the posterior margin nearly straight and the anterior concave. 

 The posterior processes of the maxillary bones are of moderate length, 

 about one-half the length of the bones themselves ; each of these is 

 armed in front with ttree canines, of nearly equal and of moderate size. 

 There is a series of short conical teeth along all the outer margin, 

 accompanied by a posterior villiform band. The mandibular}- ls fur- 

 nished with an outer series of conical teeth, gradually becoming smaller 

 in the posterior portion of the jaw ; there arc some viUifonn teeth 

 besides, near the sjonphj^sis. The vomerine teeth are arranged in an 

 anchor-shaped %alliform band, occupj-ing more than half the length 

 of the bone. The palatine teeth form a band, five times as long as 

 broad, and not extending on the pterj-goid. The tui'binal bones are 

 well developed, elongate, and slightly divergent ; they leave between 

 them a triangidar groove to receive the processes of the intermax- 

 illary bones. A short triangular portion of the ethmoid is visible 

 between the branches of the occipital crest, which in this species is 

 rather elevated, to its anterior extremity, and extends along all the 

 suture of the frontal bones. The lateral crests are relatively much 

 less developed, and the interior aiises from the middle of the space 

 between the occipital crest and the upper margin of the orbit. The 

 pra3orbital is large, ii'regularly quadi'angular, and smooth ; the re- 

 mainder of the infraorbital bones are narrow, and form the base for 

 ■e, large concave plate reaching into the interior of the orbit. 



The operculum has two obtuse points, with a notch between ; a 

 ridge on the interior surface of the operculum corresponds to the 

 lower of the points ; the sub- and intcropercidiuu are entire. The 

 limbs of the praeoperculum have a rather obliciuc direction towards 

 each other ; the angle is rounded, and furnished with obtuse denti- 

 culations. The posterior hmb has an exceedingly fine serraturc, ex- 



