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Show 72 MR. ST. GEORGE MIVART ON HEMICENTETES. [JAN. 17, CENTETID^E. I. - or -, C. g, M. |±§. Skull very cylindrical, broadest between the glenoid surfaces ; no zygoma; no postorbital process ; no process and, generally, no ridge in front of the orbit; temporal fossa large; no pterygoid fossa ; tympanic a mere ring, not forming a bulla ; paroccipital and mastoid processes; nasals more or less united ; malar imperforate ; a glenoid, but no distinct carotid foramen ; foramen rotundum one with sphenoidal fissure ; optic foramen very small, but not forming a long canal; no suboptic foramen; infraorbital canal short and wide ; lachrymal foramen opening close to, or just in front of, anterior margin of orbit; a true alisphenoid canal; no external alisphenoid canal; upper true molars each forming one triangular prism, the two external principal cusps of a qua-dricuspid molar being here represented by a single prominence ; lower true molars with very small posterior processes. Fifteen to nineteen dorsal vertebrae ; lumbar processes small; no hypapophyses in the trunk, but distinct hyperapophyses; scapula with an obtuse metacromion process ; a supracondyloid foramen to humerus ; mostlv an os intermedium ; pubic symphysis very small, sometimes widely open ; tibia and fibula distinct * ; metatarsus short; five digits to each extremity; no caecum. Hab. Madagascar and West Indies. CENTETES t, Illiger. o m Q o q q q I. !^3 or p ^ , P.M. y^. No interorbital constriction ; skull exceedingly cylindrical; posterior margin of palate thickened ; mesopterygoid fossa ending posteriorly in an excavation of the basis cranii; slightly marked prominence from the inferior margin of the mandible, and placed some distance in front of the angle ; a glenoid foramen ; posterior palatine foramen large ; no defects of ossification in palate; ascending ramus of mandible only slightly concave externally ; canines long, pointed ; apex of lower canine received into a fossa ; first upper incisor small; second upper premolar not like the true molars; eighteen or nineteen dorsal vertebrae ; a scapho-lunar bone ; an os intermedium. Hab. Madagascar. HEMICENTETES, Mivart. q q Q g I. 3^, P.M. 3^3. No interorbital constriction ; skull exceedingly elongated and tapering anteriorly; nasals partly united; infraorbital canal very short and wide ; lachrymal foramen opening just in front of the anterior margin of the orbit; mesopterygoid fossa * I presume that Echinops agrees with the other genera of the Centctidcs in this character. t De Blainville, ' Insectivores,' j>ls. iv., vi., & x.; F. Cuvier, ' Dents des M a m miferes,' no. xix.; Owen, ' Odontography,' pl. ex. fig. 6; Wagner, Schreb Sunnl" ii. p. 30, v. p. 582. ' Vi ' |