482 C. W. Andreics — Fossil Mammals from Egypt. 



The occurrence of such deposits indicates the proximity of the 

 shore-line of the Mediterranean as it existed previous to the 

 Helvetian overlap. Eocks of the same character and containing 

 a similar mammalian fauna occur in France (Sables de I'Orleanais), 

 in Switzerland, and near Eggenburg in Austria, and may be regarded 

 as contemporaneous deposits near the northern shore of the same sea. 



Brachyodus africamis, sp.n. 



The most important of the specimens from this horizon is an 

 imperfect right ramus of the mandible (No. 2,849) of a large anthraco- 

 theroid ungulate (see Plate XXIII). The region in front of pm. 3 is 

 wanting, and posteriorly the bone has been broken across 3 or 4 cm. 

 behind the last molar, so that the articulation and angle are lost, 

 and only the base of the coronoid process is preserved ; it cannot 

 be determined whether the angle was produced downward into 

 a flange projecting below the level of the ramus, or not. The molars 

 and last premolar are in an excellent state of preservation, but pm. 3 

 is represented only by its fangs implanted in their alveoli. The 

 condition both of this specimen and of others from the same locality 

 is such as to indicate that careful excavations would probably lead to 

 the discovery of very well-preserved mammalian remains. The 

 mandible in question was collected by Dr. Blanckenhorn, who pointed 

 out that it probably indicated a new species of Deperet's genus 

 Brachyodvs, for which he proposed the name B. ofricanus, a suggestion 

 which is here adopted. The genus Brachyodus was founded by 

 Deperet ^ for the reception of certain species of anthracotheroid 

 ungulates which had hitherto been referred to Anthracotherium ^ 

 or Ancodus? He takes Anthracoilierivm ovoideum of Gervais^ as the 

 type of the genus, and describes a well-preserved mandible, together 

 with some upper teeth and a calcaneum of this species from the 

 Lower Miocene of Eggenburg. 



As far as the mandible is concerned, the chief points in which, 

 according to Deperet, Brachyodus differs from Anthracotherium, are : 

 (1) The mandibular ramus in the region of the cheek-teeth is not; 

 so deep, its lower border is curved instead of nearly straight, the 

 symphysis is less prolonged backwards and must have been less 

 elongated, and there is only one dental foramen instead of two or 

 three. (2) The lower molars are arranged in a continuous series, 

 there being no diastema between. pm. 1 and pm. 2, and at the same 

 time these premolars are shortened in correlation with the shortening 

 of the mandible. (3) In the lower molar teeth the inner tubercles 

 are higher and less massive. The outer tubercles are more com- 

 pressed in a V-shape ; the postero-external tubercle unites by its 

 anterior end with the postero-internal tubercle, as in Ancodus. The 

 talon of m. 3 is less developed, and bears a single tubercle only, 



1 Deperet, " Ueber die Fauna von Miocanen Wirhelthieren aus der ersten Medi- 

 terranstufe von Eggenburg " : Sitz. k. Akad. Wiss. Wien, Bd. civ (1895), p. 397. 



2 Gervais: Zool. et Pal. franc;., I'' ed., t. i, p. 96 ; 2^ ed., p. 190. 



•' Neumavr, " Hyopotamtts-TeBte von Eggenburg": Verb. Geol. Eeichsanstalt, 

 1883, p. 283. 



