Miscellaneous. 75 



The vertebrae are kno-Rii from isolated and connected specimens 

 which indicate a larger number than usual of rib-bearing presacral 

 vertebrae, which appear to be not fewer than nineteen, and may have 

 numbered twent5--six. The sacral vertebra? are deeply cupped, and 

 the sacral ribs are developed as in NotJwsaurus and Pareiasaurus. 

 The sacral ribs form part of the articular face of the first sacral 

 vertebra. The pelvis is imperfectly known ; the ilium is not so 

 extended as in Dicynodonts, and conforms to the type of Phoco- 

 saui-Hs. which is regarded as Theriodont. The pubis and ischium 

 are united together on the Dicynodont plan, but are only moderately 

 developed. 



The scapular arch is completely known, and is formed of scapula, 

 coracoid, and pre-coracoid as in D'lCijnoiJon and Pareuisaurus. The 

 humerus and bones of the fore limb were relatively short, and only 

 fragments have been preserved which appear to be referable to ulna 

 and radius. 



The hind limb is known from several examples of the femur, 

 which resembles that of Pareiasaurus in the proximal end, but at 

 the di-tal end is more like the type described as Saurodesmus. 



The tibia is known from its proximal and distal ends; it has a 

 general resemblance to that of Pareiasaurus, but is more slender. 

 These types are regarded as constituting a distinct group, named 

 Deuterosauria, which is in many respects intermediate between the 

 Piacodontia and Theriodontia, but in skull structure appears also to 

 approach Nothosaurs and Plesiosaurs. — From the Proceedinr/s of 

 the Po>/al Socidii, June 10th, 1893. 



On a Terrestrial Leech from Chili. By M. Raphael Blancharu. 

 The discovery of a species constituting a transition between two 

 groups of animals which were previously quite distinct deserves to 

 attract in a special manner the attention of natui'alists. This is 

 why we think it our duty to report to the Academy the existence of 

 a Hirudinean which is clearly intermediate between the Glossi- 

 phonidie and the Hirudinidce. 



The animal in question is a land-leech, which is distributed in 

 the south of Chili, between latitudes 40° and 43°, in the provinces 

 Valdivia and Chiloe. In 1871 it was briefly described by Grube 

 under the name Ilirudo brevis ; but it may be said that this author 

 failed to recognize any of the remarkable characters which the 

 creature exhibits and which give it a high impoitancc from the 

 point of view of the genetic connexion of the different species. 

 This leech cannot ])e retained in the genus ////-(u/o as it has recently 

 been defined by the investigations of "Whitman and ourselves. We 

 create for it the new genus Mesohdella ; this name serves to recall 

 the fact that the species which we are discussing is intermediate 

 between two dilha-cnt groups. In future, tlierefore, it should be 

 designated MesohdcUa brevis, Grube. 



A.S contracted by alcohol the animal is 10 millim. in length aiul 

 4'5 millim. in width ; the posterior sucker is circular and 2 millim. 

 in width. The body is pyriform in appearance, as in the majority 

 of the Glossiphouida), but it is not so decidedly flattened as in the 



