284 PHILOSOPHICAL TRANSACTIONS. [aNNO 1 /QS. 



COW, and as large; these become turgid when the penis is erected. The whole 

 of this is contained in the prepuce, and may be considered as glans. 



From the os pubis arises a strong muscle, which soon becomes tendinous. 

 This tendon is continued along the back, or upper part, of the penis; it is flat- 

 tened, is about the size of a man's little finger, and is inserted into the upper 

 part of the glans, near the end. The use of this muscle is to straighten the 

 penis. On the under side of the penis there are 2 muscles, antagonists to the 

 above; they arise from the os ischium fleshy, run along the lower side of the 

 penis, on each side of the corpus spongiosum, and are inserted fleshy into the 

 lower side of the glans. The action of these muscles will draw in the penis, and 

 bend it. The male has 2 nipples, like the female, situated between the hind legs, 

 they are about half an inch in length, of a pyramidal form, rounded at the end. 



The whole skin of the animal is rough, and covered very thinly with short 

 black hair. The skin was not more than 4- of an inch in thickness, at the 

 strongest part; under the belly it was hardly -f of an inch; any part of it might 

 be cut through with ease, by a common dissecting knife. The animal had not 

 that appearance of armour which is observed in the single horned rhinoceros. 

 After Mr. B. had dissected the male, he had an opportunity of examining a fe- 

 male, which was more of a lead colour ; it was younger than the male, and had 

 not so many folds or wrinkles in its skin, of course it had still less the appear- 

 ance of armour. The only external mark which distinguishes it from the male 

 is the vagina, which is close to the anus; whereas in the male the opening for 

 the penis is 18 inches below the anus. 



PI. 2, fig. 9, represents the entire animal; fig. 10, the cranium; fig. 11, the 

 upper and under jaw, separated from each other. 



///. Description of a Species of Chcetodon* , called, by the Malays, Ecan bonna. 

 By Mr. IVilliam Bell, Surgeon in the Service of the East India Company, at 

 Bencoolen. p. 7- 



The fish called ecan bonna, by the Malays, is broad, flat, and of a lead 

 colour ; the belly is flat, white, and in places tinged with green. The eyes are 

 a bright yellow. The body is covered with small semicircular scales. Its length 

 generally about 18 inches; its breadth 13, and, at the thickest part, it is nearly 

 3 inches thick. It is frequently caught at Bencoolen, and several other parts on 

 the west coasts of Sumatra, and is said to grow to a much larger size. Its flesh 

 is white, firm, and well flavoured, and it is considered as a good fish for the table. 



• Chaetodon ecan bonna. C. subquadratus plumbeus, abdomine albido, pinna dorsalis unica, 

 Cauda subiategra. Squarish lead-coloured chaetodon with whitish abdomen, single dorsal fin, and 

 nearly even tail. 



