. The Annals and magazine of natural history; zoology, botany, and geology. Natural history; Zoology; Botany; Geology. Prof. H. G. Seeley on the Ornithosaurian Pelvis. 247 Fisr. 7. which would lead me to doubt its being an articular facet. In the Pterodactylia the prepubic bones are never anchylosed together. On the other hand, the other pelvic bones are commonly anchylosed together in genera from the Lias and Oolites. In Pt. dubius there may be some ground for doubt whether the pubis and ischium are not really one bone, as von Meyer believed, because ossification appears to be incomplete, and
. The Annals and magazine of natural history; zoology, botany, and geology. Natural history; Zoology; Botany; Geology. Prof. H. G. Seeley on the Ornithosaurian Pelvis. 247 Fisr. 7. which would lead me to doubt its being an articular facet. In the Pterodactylia the prepubic bones are never anchylosed together. On the other hand, the other pelvic bones are commonly anchylosed together in genera from the Lias and Oolites. In Pt. dubius there may be some ground for doubt whether the pubis and ischium are not really one bone, as von Meyer believed, because ossification appears to be incomplete, and yet the two bones are blended, without trace of suture; but it is more probable that ossification has obliterated the suture. It is these circumstances which led me to adopt the view that the ventral part of such an ischio-pubis would have a tendency to be limited to the ischiac region, because the pubic part, freed from the usual mechanical stimulants to ossification, would have a tendency to undergo atrophy and shorten more and more, until the prepubis was brought into contact with the prominence which alone remained to mark the position of the pubis, as in Crocodiles. In the Khamphorhynchidse * the prepubic bones are much more unsymmetrical, and commonly have the form of a capital Y (figs. 7,8), in which one limb of the fork is reduced in length or may be absent, though the latter condition may be a generic difference. In this family the pelvis is relatively small ; the anterior pro- cess of the ilium is relatively deep and in marked contrast with the rod-like anterior process of other family types. My own notes, written from the specimens at Munich, are as fol- lows :— "'Bhamphorhynchus 3Iiinsteri} var. longimanus (Wagner). — The pre- pubis is shaped something like a boomerang and measures 1-gV inch from end to end. It is angular in front, with a projecting process in about the middle of the lateral bor- ; In other species this angular process is absent,
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