APEIL 16, 1897.] 



SCIENCE. 



631 



tain endoderm cells, to overgrow in the J and 

 J embryo all sides of these cells and thus com- 

 pletely enclose them, unless ' regeneration ' or 

 ' postgeneration ' occurs. Consequently Mr. 

 Crampton's so-called J and \ embryos have at 

 least made an attempt to become whole em- 

 bryos, and Crampton and Wilson are wrong 

 when they state that the power of ' regenera- 

 tion ' or ' postgeneration ' is entirely absent. 



A number of other points in this work were 

 mentioned as affording evidence against instead 

 of for the mosaic theory, even as modified by 

 Wilson. 



In general terms, the oblique cleavage is, of 

 course, the result of the organization of the egg. 

 It may be pointed out that it is the form of 

 cleavage which brings each cell into contact 

 with the greatest number of other cells. It is 

 certainly not ' mechanical ' in Wilson's sense, 

 for even the constant direction of obliquity 

 cannot be explained in this way. 



O. Hertwig's view of the organization of the 

 «gg cannot be regarded as sufficient to explain 

 the facts. Examples were given showing the 

 •extreme differences in the allotment of yolk in 

 ■different species even when the yolk was simi- 

 larly placed in the unsegmented egg. There is 

 an organization more fundamental than the 

 visible one, which governs both the form of 

 cleavage and the position of yolk in the blas- 

 tomeres. 



The egg appears to be a complex of sub- 

 stances possessing the power to produce an 

 ■embryo and through this an adult, by a series of 

 processes not as yet understood. Visible locali- 

 zation in the egg or early cleavage stages, 

 which is only a localization of protoplasm and 

 deutoplasm, does not necessarily imply a corre- 

 sponding location of the morphogenetic factors. 

 The facts rather appear to indicate that what 

 we call the morphogenetic factors are the pro- 

 cesses going on in the egg as a whole. Any 

 strictly cellular theory of development must be 

 inadequate, as Dr. Whitman has shown. 



In the final analysis the organization of the 

 ■egg is dependent on the structure of the ' idio- 

 plasm.' This would seem to favor Dr. Whit- 

 man's view that the egg has a definite organi- 

 zation from the start. The localization of 

 protoplasm and deutoplasm, however, which 



we find in the mature egg must be acquired 

 during ovigenesis. C. M. Child. 



TOBREY BOTANICAL CLUB, MARCH 9, 1897. 



The Secretary announced the conditions of a 

 grant now offered from the funds left by Pro- 

 fessor Newberry for encouragement of research, 

 to be supplied successively to zoology, botanj', 

 geology and paleontology. For the present 

 year the award is offered in geology or paleon- 

 tology to amount to $50.00, payable July 15, 

 1897, the competitors to belong to the Scientific 

 Alliance of New York City. 



The scientific program was then taken up, 

 the evening being devoted to the subject of 

 ferns, with papers as follows : 



1. Mrs. Elizabeth G. Britton, ' Notes on some 

 Mexican Ferns,' presented in Mrs. Britton's 

 absence by Dr. Eusby, with exhibition of nu- 

 merous specimens, including species of Pellsea, 

 Polypodium, Cystopteris and Cheilanthes. Dr. 

 Rusby, having been himself present at their 

 collection, described vividly the tongue of hard, 

 black lava on which the collectors walked, and 

 which was filled with large cavities often form- 

 ing caves, containing some accumulation of soil 

 and crowded with a luxuriant growth of ferns, 

 although in November and practically the win- 

 ter season. 



2. Mr. Willard N. Clute, ' The New York 

 Stations for Scolopendrium.' Mr. Clute con- 

 trasted the wide distribution of the Hart's- 

 tongue fern in the old world, from the Azores 

 to Japan, with the extremely local North 

 American occurrence, in five areas only, 

 Mexico, Tennessee, central New York, Owen 

 Sound, in Ontario and New Brunswick. The 

 central New York locality was made known 

 early in the present century through John 

 Williamson, and was visited by Pursh in 

 July, 1807, who found it five miles west 

 of Syracuse on the farm of J. Geddes, where 

 it has recently been rediscovered. About 

 1827 Wm. Cooper discovered it at Chittenango 

 Falls, where Mr. Clute found hundreds of plants 

 growing last summer. Mr. Clute described the 

 Chittenango ravine and its ferns. On sunny 

 exposures of the limestone walls of the ravine 

 grow rue spleenwort and purple cliff-brake in 



