764 



REPOBT 1884. 



mm 



pre-sacral vertebra} hoJIow ; cnch sacral vertebra supjiorts its own transverse pro- 

 cess. Fore and liiud l.nibs nearly equal ; limb bones solid. Feet plantiiiradc, un- 

 gulate ; five digits in manus and in pes; second row of carpal and tarsal lioni's 

 unossitied. Sternal lioues purial. I'ubes projectinjj in front, and united dij-tullyliy 

 cartilage; no post-pubis. 



I. Family Atluntosauridcp. A pituitary canal. Ischia directed downward 

 with expanded extremities meeting on median line. Sacrum hollow. Anterior 

 caudals with lateral cavities. 



Genera : Atlantosanrufi, Apatosaurus, Urontosnunis. 



'2. Family Diplodotuhf. Dentition weak. Brain inclined backward. Lari-e 

 pituitary fossa. Two antorbital openings. Ischia with straight shaft, not expandtd 

 distally, directed downward and l)ackward, with ends meeting on median line. 

 Caudals deeply excavated below. Chevrons with both anterior and posterior 

 branches. 



Genus : Diplodocus. 



3. Family Mur'ii^annd(r. Small pituitary fossa. Ischia slender, with twisted 

 shaft, directed backward, and sides meeting on median line. Sacral vertebne sohd. 

 Anterior caudals solid. 



Genus : Moro^aunti'. 



European forms of tliis order: Buthrioxpondyhuo, VHiosmiruif, C/cimJrosico- 

 sdiinis, Eucitmcrutua, Ornitltopsis, I'l'lorusauins, 



II. Order S'ieuosaxtki.v (Plated Lizard). Herbivorous. Feet plantigrade, 

 ungulate ; tive digits in manus and in pes; second row of carpals unossitied. Tubes 

 projecting free in front ; post-pubis present. Fore limbs small : locomotion 

 mainly on liind limbs, (,'ervical ribs free. Vertebne and limb bones solid. 

 Osseous dermal armour. 



1. Family Stegosuurida: Vertebraj bi-concave. Neural canal in sacrum ex- 

 panded into large chamber ; ischia directed backward, with sides meeting on 

 median line. Astragalus coiissilied with tibia ; mctapodials very short. 



Genera: iSfef/osaiints (IIi/j7sir/iop/ius), iJiracodoii, and in Europe (J/iiosaunis. 



1*. Family IScelidomuridef, Astragalus not coiissiiied with tibia ; metatarsals 

 elongated; four functional digits in pes. Known forms all ]']uropean. 



Genera: Scclidosaurns, Av(nithopholis, Crataomui', JlyUeosaiirus, I'olucanthus. 



III. Order ORNiXKoron.v (Bird-foot). I'remaxillaries edentulous in front, A 

 preraandibular bone. Herbivorous. Feet digitigrade, five functional dijiits in 

 manus and three in pes. Pubes projecting free in front ; post-pubis prnseut. 

 Vertebrae solid. Cervical ribs free. Fore limbs small ; limb bones hollow. 



1. Fann\y Campfosaurtd(e. Clavicles wanting ; post-pubis complete. 

 Genera : Vamptosaunis, Litomurns, Nanomurus ; and in I'jurope Jlypsilophodiii. 



2. Family Ljuanvdontida. PremaxillaviesedentulouSj Post-pubis incomplet". 

 Known forms all European. 



Genera : Iijunnodon, Vcttimurux. 



?>. Family Iladromturhhe. Teeth in several rows, forming with use a tesselated 

 grinding surface. Anterior vertebra) opisthoccelian. 



Genera : JIadrosaurus (Uiclonius), 'i Ayathaumas, Vionodon, 



IV. Order Tiieropoda (Beast-foot). Carnivorous. Premaxillary bones with 

 teeth. Anterior nares at end of skull. Large antorbital opening, \'erteline 

 more or less hollow. Limb bones hollow. Feet digitigrade ; digits witli prelieiisile 

 claws. Pubes projecting downward, with distal ends coossitied. 



1. Family Meyalosauridec. Anterior vertebne convexo-concave ; remaiiii"!: 

 vertebrm bi-concave. Pubes slender. Astragalus with ascending process. 



Genera: Megalosaurus i^roikilopleuron), Allosaurus, Coelosaurii/', CnosaurM, 

 Dryptosaurus i^Lcelaps), 



"2. Family Labrosuuridce, Lower jaws edentulous in front. Cervical and 

 dorsal vertebne convexo-concave. Pubes slender, with anterior margins united. 

 Astragalus with ascending process. 



Genus : Lnhrosmunis. 



3. Family Zanelodojitida. Vertebrae bi-concaye. Pubes broad elongate plates, 



