230 



PROCEEDINGS OF THE ACADEMY OP 



The families of the last tribe differ as follows : 



a. Two suspensoria; nostril in the rostral shield. Tongue squamous. 

 Eye concealed by epidermis ; occipital segment loosely 



attached. No frontal under-arch An ely tr opidje .* 



Eye distinct ; occipital closely articulated ; two premax- 



illaries Acontiida?. 



B. One suspensorim ; nostril in a nasolabial plate ; tongue papillose. 

 Eye distinct; occipital closely articulated; one premax- 



illary ; an inferior frontal arch Anielli d se. 



In the first family enter Typhlosaurus, Feylinia, (much the same is Typhlo- 

 scincus) and Anelytrops. In these the columella is well developed. In Ane- 

 lytrops there is a long squamosal articulated to the side of the parietal, as in 

 Rhineiira and Cephalopeltis, the premaxillary is single, and palatine lamina? 

 of the maxillary are dilated. The spleniomental groove is open. There are 

 two slender clavicles united medially and giving insertion to the thoracic 

 hsemapoyhyses. These, according to Rathke, are present, but not in contact 

 in Acontias, and Peters and Stannius failed to find them in Typhlosaurus. 

 The pelvis I find to be represented by an oblique bone at the extremities of two 

 pairs of ribs on each side of the vent. 



The remarkable genus Amelia lacks the squamosal and columella, and has 

 a single premaxillary. The parietal is continuous with the superior plate of 

 the temporal, and is much decurved toward the sphenoid ; the frontal en- 

 closes the olfactory lobes below ; these characters are the most amphisbfenian 

 in the order. There are small pre- and postfrontal bones, and a slender ligamen- 

 tous postorbital arch. I have as yet found no sternal pieces, and the splenio- 

 mental groove is closed, as in Acontias. 



The Ophidian suborders may be briefly summed up as follows : 



*. Mastoid part of cranial walls : coronoid bone present. 



I. No ectopterygoid. No prefontal. Maxillary without 



alveolar ridges or malar process. Rudiments of 



pelvis without pubis Scolecophidia. 



II. No ectopterygoid. Prefontal present. Maxillary with 



alveolar ridge and malar process. Rudiments of 



pelvis with pubis Catodonta.| 



III. An ectopterygoid, and prefrontal. Maxillary with 



alveolar ridges and teeth, horizontal, in contact 



with prefrontal Toetkicina. 



B. Rudimentary posterior extremities Tort r icid a?. 



8B. No rudiments of extremities Uropeltida. 



aa. Mastoid not entering cranial walls, projecting. Ectopterygoid present. 



IV. 0. maxillare horizontal, produced to premaxillare, 



provided with solid teeth. No rudiments of pelvis. Asinea. 

 a. Coronoid present ; rudimental posterior extremities. 

 Coronoid and articular very elongate-slender. No 



postorbital or supraorbitals ; premaxillary teeth. Xenopeltidse. 

 Coronoid and articular short ; post- and supraorbitals 



and premaxillary teeth Pythonidse.t 



Coronoid and articular short ; postorbitals ; no supra- 

 orbitals or premaxillary teeth Boid se . 



8. Coronoid bone wanting ; no rudimental extremities. 



* Typhlinidre Gray. The name Typhline is preoccupied. 



t Vid. the important discovery of the pelvis by Peteis, Monatsbe, Berlin Ac, 1863, 270. 

 j Loxocemus enters this family rather than the next. Giinther is right in assigning premax- 

 illary teeth ; posterior extremities,, absent in his young specimen, are present in adults. 



[Oct. 



