664 MR. M. JACOBY ON NEW [NoV. 1, 



timis, characterized by the preat length of the rostrum and the 

 extreme compression of the dental alveoli. The occipital region is 

 more like that of the Caucasian fossil than is Pontistes, but there is 

 not the square flat surface behind the nostrils ; while the dental 

 alveoli are quite different from those referred to the Caucasian form. 



None of the other fossil forms referred to the Platanistidce, of 

 which the skulls are known, have the maxillary fossiB of the Inia 

 type ; and I accordingly regard the Caucasian skull as indicating a 

 new genus and species, for which I suggest the name Iniopsis 

 caucasica. 



The evidence that the Platanistidce are a very ancient type has 

 been gradually accumulating ; but the European Tertiary forms 

 hitherto referred to that group have more Dolphin-like skulls. The 

 occurrence of a form so closely allied to the South-American types 

 in Russia is therefore a matter of considerable interest. Its associ- 

 ation with the North-American Tertiary genus Zeuc/lodon is also 

 significant, and suggests that both these groups of Cetaceans had 

 originally a wide distribution. 



P.S. — Since this paper was in type I have received from Dr. Sjogren 

 a copy of an article' in which the Cetacean-yielding strata of the 

 Caucasus are assigned to the Eocene. 



EXPLANATION OP THE PLATES. 



Plate XXXVI. 



Fig. 1. Inner side of hinder part of the left ramus of the mandible of 



Zcuglodon caucasicus. \. 

 Fig. 2. Dorsal aspect of left humerus of the same, h, head ; t, greater tuber- 

 osity ; d, deltoid ridge; r, radial facet ; ii, ulnar facet. {. 

 Fig. 3. Inferior aspect of imperfect caudal vertebra. \. 



Plate XXXVII. 

 Figs. 1, 1 «. Anterior and right lateral aspect of centrum of posterior cervical 



vertebra of an undetermined Cetacean (^Platanistidce). a, upper, 



b, lower transverse process. \. 

 Figs. 2, 2 a. Anterior and inferior aspects of anterior caudal vertebra of the 



same. \ . 

 Figs. 3, 3 a. Fragment of jaw of (?) Iniopsis caucasica. \. 



Plate XXXVIII. 

 Fig. 1. Frontal aspect of imperfect cranium of Pontistes rectifrms. |. (After 



Burmeister.) 

 Fig. 2. Corresponding view of imperfect cranium o? Iniopsis eaiecasica. |. 



5. Descriptions of some new Genera and new Species of 

 Phytophagous Coleoptera from Madagascar. By 

 Martin Jacoby, F.E.S. 



[Eeceived September 1, 1892.] 

 (Plate XXXIX.) 



But little is known at present ofthe Phytophagous Coleoptera of 

 Madagascar, especially so far as the smaller species are concerned, 

 and it is probable that many interesting forms will be found by a 

 ' Meddel. Upsala Univ. Min.-Geol. Inst. vol. xiii, arts. 2, 3 (1891). 



