1904.] ON NEW FISHES FROM THE NIGER. 197 



artery to arise from the basilar behind the sixth nerve. I have 

 noted as exceptions only Tragulus meminna and Gazella rufifrons, 

 which in this point agree with Man *. 



(4) The circle of Willis is generally, but not always, entirely 

 symmetrical in itself and in its branches. When it is incomplete, 

 as e. g. Hyrax (posteriorly) and Lagostomus (anteriorly), or asym- 

 metrical (e. g. ophthalmic arteiy in Alyopotamus), the advantage 

 lies with the left side. 



(5) A rete is occasionally (e. g. Tamandua) formed between the 

 circle of Willis posteriorly and the pituitary body in front. 



(6) The brain of Hyrax has an arterial system constructed upon 

 the Ungulate plan, and is especially like the Horse. 



(7) Tamandua shows characters which are elsewhere found in 

 the Carnivora in respect of the I'homboidal area sui-rounded by 

 equisized vertebral and anterior spinal arteries. 



(8) The Arctoid Carnivora can apparently be distinguished 

 from the ^-Eluroid Carnivora by the mode of origin of the callosal 

 arteries. In the former they arise nearer to the circle of Willis 

 and fuse to form a single artery. In the latter the arteries are 

 given ofl* later and do not fuse ; but there is a communicating 

 artery which joins the two cerebrals before they give off the 

 callosal. It is clear, therefore, that the circle of Willis may be 

 completed anteriorly by arteries which are not homologous. 



o. Descriptions o£ Three new Fishes discovered by the late 

 Mr. J. S. Budgett in the Niger t- By G. A. Boulenger, 

 F.R.S., V.P.Z.S. 



[Received December 17, 1903.] 

 (Plates VII. et VIII.J) 



Marcusenius budgetti. (Plate VII. fig. 1.) 



Depth of body 3 times in total length, length of head 5 times. 

 Head a little deeper than long ; snout rounded, 4 length of head ; 

 mouth small, inferior, its width 4- length of head ; teeth small, 

 notched, 5 in the upper jaw, 6 in the lower ; anterior nostril on 

 a line with the lower border of the pupil and equally distant from 



* I do not suggest at present that this is an Ungulate character since my material 

 is obviously too scanty. Hyrax does not agree with Traqidtts and Gazella. 



t This note was intended to supplement an account by Mr. Budgett of his 

 expedition to the Niger in quest of the eggs of Polypterus, which was to have been 

 read before this Society at the Januarj' meeting. In the meantime Science has had 

 to deplore the loss of this gifted and courageous zoologist, who died on Jan. 19, on the 

 very evening his paper was annoi\nced for reading, from fever contracted on his 

 expedition. — G. A. B. 



'^ For explanation of the Plates, see p. 199. 



