262 Hohcrf Bell — Land-Shells in the Heel Crag. 



(3.) Family Labrosauridw. Lower jaws edentulous in front. Cervical and dorsal 

 vertebrfe convexo-concave. Pubes slender, with anterior margins united. 

 Astragalus with ascending process. 

 Genus, Labrosaurus. 

 (4.) Family Zandodontidce. Vertebrfe bi-concave. Pubes broad elongate plates, 

 with anterior margins united. Astragalus without ascending process. Five 

 digits in manus -and pes. 



Genera, Zanclodon, ? Teratosaurus. 

 (5.) FmnHj Amphisattridce. Vertebra) bi-concave. Pubes rod-like. Five digits in 

 manus, and three in pes. 



Genera, Amphisauriis{Megadactylus), ? Bathygnathus, ? Clepsysaurus, Palceo- 

 saurus, Thecodontosaurus. 



Sub-order Cceltjuia. 

 (6.) Family Cwluridce. Vertebra) and bones of skeleton pneumatic. Anterior 

 cervicals convexo-concave ; remaining vertebra) bi-concave. Cervical ribs 

 coossified with vertebrae. Metatarsals very long and slender. 

 Genus, Ccelnrus. 



Sub-order Compsognatha. 

 (7.) Y?imi[Y Compsognathidm. Cervical vertebrae convexo-concave ; remaining verte- 

 brae bi-concave. Three functional digits in manus and pes. Ischia with long 

 symphysis on median line. 

 Genus, GonqJiognathiis. 



Of these seven well-marked families, the Amphisauridce and 

 Zandodontidce are Triassic, the MegalosauridcB are Jurassic and 

 Cretaceous, while the others are all Jurassic alone. 



There are still some very diminutive carnivorous Dinosaurs that 

 cannot at present be referred to any of the above families ; but this 

 may in part be due to the fragmentary condition in which their 

 remains have been found. 



The peculiar orders Hallopoda and Aetosauria include carnivorous 

 reptiles which are allied to the Dinosauria, but they differ from that 

 group in some of its most characteristic features. In both Aetosaurus 

 and Hallopus, the calcaneum is much produced backwards. In the 

 former genus, the entire limbs are crocodilian, and this is also true 

 of the dermal covering. In Hallopus, the calcaneum is greatly 

 lengthened, and the whole posterior limb is especially adapted to 

 leaping. In both of these genera, there are but two sacral vertebrEe, 

 but this may be the case in true Dinosaurs, especially from the Trias. 

 [Future discoveries will probably bring to light intermediate forms 

 between these orders and the typical Dinosaurs. 



III. — Land Shells in the Eed Crag. 



By Egbert G. Eell, F.G.S. 



PERHAPS very few Tertiary formations have received a greater 

 amount of attention from geologists and collectors of fossils, 

 during the last forty years, than the Ked Crag of Suffolk and 

 Walton-Naze ; and it seems singular that so few traces of land life 

 have resulted from so much research. Although in its southern 

 portions it is strictly a marine deposit, yet its distance from shore 

 could not have been very great at any point ; but putting aside the 

 few plants and mammalian remains, most of which in the coprolite 

 portion of the Eed Crag are derivative, there is little evidence of its 

 proximity. 

 In that part of Suffolk near Chillesford and around the small 



