Relations of Symmetry in the Developing Ear of Amblystoma Punctatum.

MORPHOGENESIS AND METABOLISM O F AbIPHIBIAN LARVAE AFTER EXCISION OF HEART

In the previous paper of this series (Remp, '53) it was reported that tadpoles of Rana pipiens would live up to 6 days at room temperature after excision of heart at Shumway stage 22 or 23. Because of the obvious differences between anuran and urodele larvae in form and rate of development, the experiment was repeated on Amblystoma punctatum at Harrison stage 40, 41 o r 42 (Kemp and Quinn, '51)...

Return of Vision in Larval Eyes Exchanged between Amblystoma Punctatum and the Cave Salamander, Tryphlotriton Spelaeus.

The Effect of Replantation, Lens Removal, and Optic Nerve Section of the Eye of the Salamander (Triturus Viridescens) *

In 1885 Bradford replaced the atrophied eye of a 35-year-old sailor with the eyeball of a rabbit and reported a good cosmetic result without return of vision. Two years later May attempted, without success, to duplicate this result and conduded that the whole eyeball was too large a mass to transplant with the hope of retaining vitality in all of its parts. Gradually work turned from man to the...

Grafted Eyes of Young and Old Adult Salamanders (Amblystoma Punctatum) Showing Return of Vision *

These experiments are part of a series which the senior author has been making on the grafted vertebrate eye in fishes, amphibians, and mammals. In all of the vertebrates studied the eyes were completely excised and then eith-er reimplanted in the same orbit or transplanted to the denuded orbit of another host. In placing the graft, care was taken to re-establish the normal orientation. In the ...

Optimization of Conformal Mapping Functions used in Developing Closed-Form Solutions for Underground Structures with Conventional cross Sections

Elastic solutions applicable to single underground openings usually suffer from geometry related simplification. Most tunnel shapes possess two axes of symmetry while a wide range of geometries used in tunneling practice involve only one symmetry axis. D-shape or horse-shoe shape tunnels and others with arched roof and floor are examples of the later category (one symmetry axis). In the present...