686
PROF. OWEN ON THE RANK AND AFFINITIES IN
mosal, 27, for the suspension of the tympanic, 28 ; the pair of hypa-
pophyses, i', from the basioccipital, i ; the greater proportion of the
occipital surface contributed by the median part of the coalesced
Fig. 2.
Amblyrhynchus.
Occipital region of skull.
parietals, 7, and by the lateral extensions, 7', which are relatively
greater ; the mastoid, 8, moreover, is pushed inwards by the junc-
tion of 7' with 27 ; finally, the large vacuities between 7' and 2-4 *.
An extreme modification of the occipital is shown in the Ophidian
reptiles. In Python reticulatus the basioccipital forms the lower
part of the condyle, fig. 3, 1, supported on a short peduncle, on each
Fig. 3.
Fig. 4.
Pytkon.
Back and side views of occipital region of skull.
side of the base of which is a low transverse ridge for attachment of
the capsular ligament. The siugle hypapophysis is shown at i'„
The exoccipitals (2) contribute the upper and lateral portions of the
condyle, and unite together above the occipital foramen. Each ex-
occipital has a small process supplementing that from the basioccipital
for the attachment of the strong capsular ligament of the occipito-

• These characters are well shown in the corresponding view of the same
  

species in Steindachner's Monograph, pi. v. fig. 8 ; but the constituent bones are
not indicated, and the suture between the mastoid and parietal is omitted on the