Reviews 



CRYPTOZOON. REPLY TO THE REVIEW OF C. W. W. 



Before the genus Cryptozoon is relegated to the indiscriminate heap 

 of concretions, as proposed by the reviewer C. W. W. in the Journal of 

 Geology (Jan.-Feb., 1908, p. 85), facts Uke the following ought to be con- 

 sidered : 



This form — Cryptozoon or Concretion ? — is found like concretions 

 in wide apart localities, but unlike concretions it occurs only in connection 

 with a certain geological formation, the Beekmantown, and in this forma- 

 tion it is restricted to a narrow horizon, only two of the five divisions, so 

 far as observed, containing it. 



The peculiar character of its concentric bands in the spherical or sphe- 

 roidal masses so marked it that for a long time it passed as a Stromatopora, 

 and it was not until after Dr. Roeminger's careful discrimination of the 

 genus, that it was distinguished from Stromatopora. 



The minute structure is so like that of the undoubted fossil Stromato- 

 cerima, that in some cases when sections of each are placed side by side it 

 is difficult to distinguish them. 



Passing by other indications of the organic origin of the form, it should 

 be added that the conclusions of Mather, Hall, and Dawson should have 

 some consideration. Dawson's views were based on the study of many 

 sections of what he came to regard as good species of Hall's genus Crypto- 

 zoon. Such facts and considerations forbid the dropping of the genus 

 Cryptozoon. 



In the matter of ova an interrogation point should have followed the 

 figure, as it was designed as a suggestion, rather than a demonstration. 

 Thus one making slices of Stromatocerium finds in the microscopic field 

 distinct lacunae. In some of these exist minute spherical masses, appar- 

 ently more compact than pilae. Now it may never be possible to prove 

 that these little spheres actually are; that they may be ova, however, is 

 not an improbable suggestion. 



H. M. S. 



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