i',\0 ^Ir. G. A. Boulonger on n^rc 



interest, mil of wliich specimens are now preserved in tlie 

 Natural History Museum. 



The examples of the first two species here described, 

 together with a sin<Tle specimen of Mi/rojJus p'inctatus, LUtk., 

 a species known from the mouths of rivers on botii sides of 

 the Atlantic between the tropics, were obtained high up the 

 ]{iver Mansoa at a place called Port ]\Iansoa, and under rather 

 curious circumstances, as related by Dr. Ansorge : — 



" The presence of the tide at the mouth of this river banks 

 up tlie water in these higher regions much as a canal-lock 

 tills up a waterway till there is enough to float down a barge. 

 On arrival at Port Mansoa we found a broad deep rivei', and 

 from our steamer's side we stepped into a canoe moored to 

 the bank and walked ashore ; but at ebb the steamer lay 

 embedded in very adhesive bluish-black mud about a third of 

 the way doAvn a steep-sloping mud-bank, and the broad river 

 of our arrival had dwindled into a narrow stream about 

 15 feet broad at the bottom of a deep gully bounded by two 

 large sloping mud-banks. 



'^ I saw a number of native boys plunging about in this 

 mud, and found they were catching eel-like fishes with their 

 hands. Two of the three sj)ecies seemed fairly rare, as I 

 secured only one specimen of the wdiite one \_Myro'plds] and 

 only three of the black one [Synihranchus], The tiiird and 

 largest species \_Gobioides] seemed common, and I selected a 

 few.— 8 May, 1909." 



Examples of two species, Eleotris africanus, Steindachner, 

 and a new Gobius of the subgenus Oxyurichthys, Bleeker, 

 were obtained in the Gunnal River, which flows at right 

 angles into the right side of the Cacheu River, and comes 

 from the direction of the French possessions. 



Symbranclnis ofer. 



Snout rounded, about twice length of eye and a liitle 

 exceeding interorbital width; the distance between end of 

 snout and gill-opening is 1^ times length of skull, 8 times 

 length of snout, and is contained 7f times in distance trom 

 snout to vent; length of tail about 3^ times in the total 

 length. Gill-opening rather wide, as in S. hengalensis. 

 Tail ending in a rather obtuse point, as in S. marinoratus. 

 126 vertebrae. Coloration uniform blackish. 



Total length 320 mm. 



Three specimens from Port Mansoa. 



Until the discovery of this species the suborder Symbianchii 



