210 Messrs. T. and A. Scott on some 



Humerus with ectepicondylar and entepicon- 

 dylar foramen ; ribs with uncinate pro- 

 cesses ; all the vertebrae with iutercentral 

 hypapophyses 4. Hattrriid^. 



Humerus with entepicondylar foramen ; ribs 

 without uncinate processes ; no hypapo- 

 physes between the dorsal vertebrae 5. Ho.ucEJSAuaiDiE. 



b. Nasal opening single. Mandible with- 

 out coronoid process, the rami united 

 in a solid S3'mphysis ; vertebrae feebly 

 biconcave ; no hypapophyses between 

 the dorsal vertebrae. Humerus with 

 ectepicondylar foramen or groove .... 6. RHyNCHOSAURiD.E. 



B. Jaws toothless. Vertebrae procoelous. 

 3Iaudible without coronoid process, the 

 rami united in a solid symphysis. Hu- 

 merus with ectepicondylar foramen .... 7. Sauranobontid^. 



References. 



(1) Baur, G.— " On the Morphology of the Skull in the Mosasauridae," 



Journ. of Morphol. vii., 1892, pp. 1-22, pis. i. and ii. 



(2) BouLENGER, G. A. — " Notes on the Osteology of Ileloderma horri- 



dum and H. sus^jectum, with Remarks on the Systematic Position 

 of the Helodermatidas," Proc. Zool. Soc. 1891, pp. 109-118. 



(3) BouLENGER, G. A. — " On British Remains of Homceosaunis, with 



Remarks on the Classification of the Rhynchocephalia/' t. c. 

 pp. 167-172. 



(4) Hollo, L. — " Nouvelle Note sur le Champsosaure," Bull. Soc. G»5ol. 



Belg. v., 1892, pp. 5-53, pis. vi.-viii. 



(5) Gorjanovic-Kramberger, C. — " Aigialosaurus, eine neue Eidechse 



aus den Kreideschiefern der Insel Lesiua, mit Riicksicht auf die 

 bereits beschriebenen Lacertiden von Comen und Lesina," Glasnik 

 Soc. Hist.-Nat. Croat, vii., 1892, pp. 74-106, pis. iii. and iv. 



(6) LoRTET, L. — " Les Reptiles fossiles du Bassin du Rhone," Arch. 



Mus. Hist. Nat. Lyon, v., 1892, 139 pp., 16 pis. 



XXXI. — On some new or rare Scottish Entomostraca. By 

 Thomas Scott, F.L.S., Naturalist to the Fishery Board 

 for Scotland, and Andrew Scott. 



[Plates VH. & VIII.] 



Paeartotrogus, gen. no v. (provisional name). 



Anterior and posterior antennae and mouth-organs as in 

 Artotrogus^ Boeck, except that the siphon is rudimentary. 

 First pair of swimming-feet with both branches two-jointed ; 



