This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1907 Excerpt: ... tive pOSltlOn as in HomO-of Macropetalichthys, viewed from the. cerebral aspect. C-margin of anterior SteUS. The pOSteriOr central; ilf-marginal;.PO-preorbital;. PiO--postorbital. Original in American moiety of this plate is seen Museum. Nat. size to be traversed by three different canal systems, identifiable with ...
Read More
This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1907 Excerpt: ... tive pOSltlOn as in HomO-of Macropetalichthys, viewed from the. cerebral aspect. C-margin of anterior SteUS. The pOSteriOr central; ilf-marginal;.PO-preorbital;. PiO--postorbital. Original in American moiety of this plate is seen Museum. Nat. size to be traversed by three different canal systems, identifiable with those called by Dean the preorbital, postorbital and occipital. Now, in the head shield of all Arthrodires so far as known, the central is the only plate traversed by all three of these canals. The preorbital and postorbital systems are sometimes confluent in other forms, but the occipital (or more properly, the exoccipito-central) does not unite with these other systems save only in Macropetalichthys. A Fig., Detached median occipital detached specimen of the median occipital show plate of Macropetalichthys showing....ensory canals and partially de-ing confluent canal systems is represented in text nuded ornamentation. Original in Mus. Comp. Zool. Nat. size figUre 2 1. Evidence of the primitive nature of this genus, as compared with other Arthrodires, is furnished by the following characters, which point to a survival of embryonic or ancestral conditions: (i) continuity of the sensory canal systems; (2) discreteness of the central elements and their separation on either side of the middle line by the median occipital; (3) reduced number of median series of plates; and (4) absence of any evidence of articulation or other connection between the head shield and dorsal body plates. We have next to speak of the configuration of the basis cranii, by which term is understood, of course, not the inner surface of the cranial buckler, but the floor and posterior wall of the chondrocranium, the passageway provided for the initial portion of the vertebral a...
Read Less
Add this copy of Devonic Fishes of the New York Formations to cart. $59.74, good condition, Sold by Bonita rated 4.0 out of 5 stars, ships from Newport Coast, CA, UNITED STATES, published 2016 by Palala Press.
