572 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
SUMMARY 
OF CURRENT RESEARCHES RELATING TO 
ZOOLOGY AND BOTANY 
( principally Invertebrata and Cryptogamia ), 
MICROSCOPY, Ac., 
INCLUDING ORIGINAL COMMUNICATIONS FROM FELLOWS AND OTHERS.* * * § 
ZOOLOGY. 
A. VERTEBRATA Embryology, Histology, and General. 
a. Embryology. f 
Inconsistencies of Utilitarianism as the Exclusive Theory of 
Organic Evolution.^ — The Rev. J. T. Gulick thinks he finds various 
inconsistencies in the exclusive use of utilitarianism as explanatory of 
the theory of evolution, and expresses his conviction that his theory 
of divergence through segregation can consistently explain them. 
Embryology of Vertebrates. §—M. F. Houssay has made a series of 
studies of the development of the Axolotl. He finds that as the ovum 
of Batracliians has a shell it incloses dense nutrient materials ; the egg 
is very large, and as a result, its segmentation is unequal. The poles 
are not previously determined. There is no epiboly ; in other words, 
the epiblast does not arise from four initial superior cells, but from all 
the peripheral cells. The pigment and size of the granules cannot be 
considered as characteristic of the elements. There is no “ hypoblast of 
invagination ” ; that is to say, the dorsal wall of the intestine does not 
come from without, but is organized on the spot ; the multiplication of 
the cells of this wall and their precocious differentiation are the result 
of the diminution of pressure caused by the increase in the dorsal epi- 
blast which is preparing to give rise to the nervous system. As the 
* The Society are not intended to be denoted by the editorial “ we,” and they do 
not hold themselves responsible for the views of the authors of the papers noted, 
nor for any claim to novelty or otherwise made by them. The object of this part of 
the Journal is to present a summary of the papers as actually published, and to 
describe and illustrate Instruments, Apparatus, &c., which are either new or have 
not been previously described in this country. 
f This section includes not only papers relating to Embryology properly so called, 
but also those dealing with Evolution, Development, and Reproduction, and allied 
subjects. 
% Amer. Journ. Sci., xl. (1890) pp. 1-14. Ann. and Mag, Nat. Hist., vi. (1S90) 
pp. 125-39. 
§ Arch, de Zool. Exper et Gen., viii. (1890) pp. 143 -244 (5 ills.). 
