scholarly journals The Relationship of Egg Shell Color to Hatchability in New Hampshires

1949 ◽  
Vol 28 (4) ◽  
pp. 577-580 ◽  
Author(s):  
E.M. Funk ◽  
James F. Forward
Keyword(s):  
Shell Color ◽  
Egg Shell ◽  
Relationship Of ◽  
The Relationship

scholarly journals The Relationship of Egg Shell Weight to Cracked Eggs

1965 ◽  
Vol 44 (6) ◽  
pp. 1513-1518 ◽  
Author(s):  
E.H. McNally
Keyword(s):  
Shell Weight ◽  
Egg Shell ◽  
Relationship Of ◽  
The Relationship

scholarly journals The Relationship between Egg Shell Color and Incidence of Colored Meat Spots

1950 ◽  
Vol 29 (2) ◽  
pp. 244-247 ◽  
Author(s):  
F.P. Jeffrey ◽  
C.E. Walker
Keyword(s):  
Shell Color ◽  
Egg Shell ◽  
The Relationship

scholarly journals The Relationship of Shell Color to Incidence of Blood and Meat Spots in Hens’ Eggs

1952 ◽  
Vol 31 (5) ◽  
pp. 855-856 ◽  
Author(s):  
W.J. Stadelman ◽  
L.S. Jensen ◽  
Martha Cyrus
Keyword(s):  
Shell Color ◽  
Relationship Of ◽  
The Relationship

The relationship of the scleractinian corals to the rugose corals

Paleobiology ◽  
1980 ◽  
Vol 6 (02) ◽  
pp. 146-160 ◽  
Author(s):  
William A. Oliver
Keyword(s):  
Critical Points ◽  
Scleractinian Corals ◽  
Convincing Evidence ◽  
Early Triassic ◽  
Rugose Corals ◽  
History Of ◽  
The Subject ◽  
Relationship Of ◽  
The Relationship ◽  
Biologic Factors

The Mesozoic-Cenozoic coral Order Scleractinia has been suggested to have originated or evolved (1) by direct descent from the Paleozoic Order Rugosa or (2) by the development of a skeleton in members of one of the anemone groups that probably have existed throughout Phanerozoic time. In spite of much work on the subject, advocates of the direct descent hypothesis have failed to find convincing evidence of this relationship. Critical points are:(1) Rugosan septal insertion is serial; Scleractinian insertion is cyclic; no intermediate stages have been demonstrated. Apparent intermediates are Scleractinia having bilateral cyclic insertion or teratological Rugosa.(2) There is convincing evidence that the skeletons of many Rugosa were calcitic and none are known to be or to have been aragonitic. In contrast, the skeletons of all living Scleractinia are aragonitic and there is evidence that fossil Scleractinia were aragonitic also. The mineralogic difference is almost certainly due to intrinsic biologic factors.(3) No early Triassic corals of either group are known. This fact is not compelling (by itself) but is important in connection with points 1 and 2, because, given direct descent, both changes took place during this only stage in the history of the two groups in which there are no known corals.

Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

1983 ◽  
Vol 41 ◽  
pp. 194-195
Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor
Keyword(s):  
High Resolution ◽  
Marine Invertebrates ◽  
Sea Urchins ◽  
Structural Features ◽  
Sea Stars ◽  
High Resolution Tem ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

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