64 MAMMALIA. 



Oetothekium (Plbsiocetcs) Hupsohi? v. bmneden. 



Mr. Lydekker (Quart. Journ. Geol. Soc, Vol. XLIII., p. 12, 

 1887) has provisionally referred to this species some vertebrae in 

 the British Museum (Cat. Foas. Mamm., Part v., p. 45, 1887), 

 and also in the Museum of Practical Geology, from the Red Crag 

 of Suffolk. The original specimens were from the Antwerp 

 Crag and were described with the last species (loc. cit.) by Prof. 

 Van Beneden, who mentions an axis vertebra Irom the Pliocene of 

 Montpeliier, the base of a cranium in the Cambridge Museum 

 from between " Sautwald " [Southwold] and Covehythe (Suffolk) 

 [ ? Norwich Crag] and a vertebra in the British Museum from the 

 Pliocene (?) near Lisbon. 



Cetotherium (Hetekooetus) brevipkons, f. beneden. 



Mr. Lydekker (Quart. Journ. Geol. Soc, Vol. XLIII., p. 12, 

 1887) having examined the type specimens in the Brussels 

 Museum refers to this small form ihree specimens from the 

 Suffolk Red Crag, namely, an "axis vertebra in the British 

 Museum and another in the Ipswich Museum, while it is not 

 improbable that a small tympanic in the latter collection may 

 also belong to this species." Prof. Van Beneden's types were 

 from the Antwerp Crag and were placed in a separate genus 

 Heterocetus. 



Genus HERPETOCETUS, V. Beneden. 



HeRPETOOETUS SriALDlENSlS, r. BENEDEN. 



Plate VI., Fig. 11a, b. . 



The lower jaw of this genus having the angle produced and the 

 articular surface on the upper part, there is some resemblance to a 

 reptilian jaw, and hence the name proposed for it by Prof. Van 

 Beneden (Bull, Ac. Roy. Belg., Ser. 2, Vol. XXXIV., p. 20, 1872 ; 

 Vol. L., p. 25, 1880; and Ann. Mug. Roy. Hist. Nat. Belg., 

 Vol. VII., Part 3, p. 84, 1882). The tympanic bone is said by 

 Mr. Lydekker (Quart. Journ. Geol. Soc, Vol. XLIII., p. 13, 

 1887) to be " readily recognised by its egg-like shape, the small 

 and sharply defined involucrum, and the iilliug-up of the anterior 

 portion of the cavity by osseous matter . . . A tympanic 

 from Red Crag [Felixstow] in the Museum of Practical Geology, 

 indicates the occurrence of Herpetocetus Scaldiensis, Van Bene- 

 den, in this country and No. 2,816 in the Museum of the College 

 of Surgeons is a second example." 



The type specimens were from the Antwerp Crag and Prof. 

 Van Beneden notices a specimen from Louvain. The British 

 specimens are from the Red Crag Nodule-bed. 



