30 



known to occur in various rivers opening into the BIght of Biafra, 

 whicli have hitherto been referred to the šame species, partly because 

 no specimens had hitherto been critically examined, and partly because 

 it seemed unlikely that two species of a genus so unprohfic, even in 

 individuals, should exist in localities so very near to each other. AU 

 probabiUty from previous knowledge, or in the absence of more pre- 

 cise or more extended information, merely j ustified a belief in the 

 existence of two species, one inhabiting the New World, the other 

 peculiar to some tropical portions of the 01d World. 



The diiFerences between M. australis and M. Senegalensis are 

 quite evident. The former seems to grow to a greater size, and the 

 shape of the skull at once distinguishes it, being altogether larger, 

 with a more lengthened nasal opening, and more elongated inter- 

 maxillary bones, giving it a large mouth. The lower jaw, also, is 

 less massive and angular, and its inferior margiu less curred. It 

 would seem to approach more to the fragmentary extinct forms de- 

 scribed by Cuvier in his * Ossemens Fossiles.' In M. Senegalensis 

 again the skull is more compact, the snout shorter, the lower jaw 

 more angular with its lower border more eurved, and the zygomatic 

 process of the temporal is less elevated. 



In 1851, while Dr. Barth was journeying towards the country of 

 Adamawa in Central Africa, he heard from the natives, accounts of 

 an animal said to freąueut the rivers and marshes named by them 

 Ayii (erroneously written Ajuh). He heard of the šame animal, 

 under the šame name, also up the river Kw(5ra or Niger below Tim- 

 buktu, and he believes that it also exists iu the river Shari, which 

 runs into the marshy Lake Tsad. Dr. Barth not having been able 

 to satisfy himself about this creature, directed Dr. Vogei' s attention 

 to it, and the latter gentleman fortunately met with a specimen in 

 September 1855 in the upper part of the Binue or Tsadda. An ac- 

 count of this Ayu having been sent by him to England, and read at 

 the British Association Meeting at Cheltenham, Prof. Owen thought 

 that it presented sufficient peculiarities to distinguish it as a species, 

 which he indicated as M. Vogelii ; but his remarks partly applied to 

 a Manatus skull, which was exhibited at the time, and which by 

 some misconception persons present had been led to consider as be- 

 longing to the very individual described by Vogei. ' 



During the months of September and October 1854 I ascended 

 the šame river ; but though this was the period when they ought to 

 have been most abundant, yet I neither saw nor heard of any such 

 animal ; and though I always carefully examined the hunting relics in 

 the various vUlages, yet I never met with its remains. From this I 

 am led to confirm Dr. Vogei' s statement, that it is a rare and scarce 

 creature. But on the 13th July previous, just after I had entered 

 the mouth of the Kwdra and Niger from the sea, I had spent the 

 day in examining some of the interminable dreary creeks, which are 

 there so apt to perplex the voyager. While returning in the after- 

 noon I saw under some paims and mangroves a coUection of miserable 

 huts, hardly entitled to the appellation of a village, towards which I 

 puUed and presently landed. The inhabitauts in great alarm all fled 



