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Show 66 MR. ST. GEORGE MIVART ON HEMICENTETES. [Jail. 17, the specimen is fully adult and the teeth even more worn than in the skull with the normal dentition, these small teeth can hardly belong to the milk-dentition. Petrodromus.-In a new specimen, in which the last molars and the upper and lower anterior incisors are not in place, I have observed the following characters :- There is no sagittal crest; the petro-mastoid, which is a single bone, is separate from the squamosal, which sends down a considerable entoglenoid process. The anterior part of the auditory bulla is formed by the alisphenoid. The petrosal has a large cerebellar fossa. A spatulate process extends backward from the middle of the hinder margin of the palate. A small foramen perforates a process of the parietal, which descends between the alisphenoid and squamosal. The rhinencephalic chamber is extensive. The second upper incisor has a small cusp at its base behind ; and the lower incisors are bilobed *. In this specimen there are but six lumbar vertebrae, and the internal condyle of the humerus is perforated. Ericulus.-There is now a complete skeleton of this form in the Museum of the Royal College of Surgeons ; and a plate representing it is here given by the kind permission of the authorities of that institution. It has 16 dorsal, 7 lumbar, 22 sacral, and about 12 caudal vertebrae. The spinous process of the axis is large, but the other cervical spines are quite rudimentary. The cervical transverse processes are not much antero-posteriorly expanded. The dorsal spines are but slightly elongated ; but those of the lumbar vertebrae are very much enlarged and antero-posteriorly extended. The lumbar metapophyses, anapophyses, and transverse processes are small; but the lumbar spines have tolerably marked hyperapophyses. There are no hypapophysial processes. The manubrium is of moderate size and not keeled. The clavicles are elongated and slender. Thus the genera of the order Insectivora yet known amount to 24 in number. INSECTIVORA. Family I. GALEorrniEciDyE: Galeopithecus. „ II. MACROSCELIDID.E : Macroscelides, Petrodromus, Bhynchoeyon. „ 111. TUTAIID-E : Tupaia, Ptilocercus, Hylomys. „ IV. ERIXACEID_J : Gymnura, Erinaeeus. „ V. CENTETID^E: Centetes,Hemicentetes,Ericulus,Echinops,Solenodon. „ VI. P O T A M O G A L I C E : Potamogale. ,, VII. CHRYSOCHLORIDJ*: : Chrysochloris, Chalcochloris „ VIII. TALPIDJJ. Subfamily I. Talpina : Scalops, Scapanus, Condylura, Talpa. „ II. Myogalina: Urotrichus, Myogale. IX SORICID^: Sorex. * As observed by Dr. Peters in his ' Reise nachMossanibique,' i. 11. 95, tab. xxii. fig. 9. |