390 Morphologie und Teratologie. 



The terms introduced by Bateson are adopted and defined, 

 and the importance of the cross DR X RR 'S emphasised. 

 The case of the Andalusian iowl is described at soine lenght. 

 Reference is made to the conception of Compound allelomorphs, 

 and an instance is given of the appHcation of this conception 

 to an actual case. 



The latter part of the book deals with the apphcation of 

 the facts previously described to current biological conceptions 

 — Variation, natural selection, mutation, and other matters are 

 referred to. The economic aspect of Mendel' s discovery is 

 alluded to and its bearing upon social questions is not forgotten. 



R. H. Lock. 



COULTER, John M. and W. J. G. Land, Gametophytes and 

 Embryo of Torreya taxifolla Arnott. (Botanical Gazette. 

 Vol. XXXIX. 1905. p. 161 — 178. Plates 1-3.) 



C o u 1 1 e r and Land report that in Torreya taxifolia 

 Arnott, each stamen bears seven rudimentary sporangia arranged 

 in a whorl. When the three adaxial sporangia reach the arche- 

 sporial cell stage the archesporial cells are replaced by resin 

 cavities. Of the four functioning abaxial sporangia, the tvvo 

 middle ones are the largest. The male gametophyte produces 

 no prothallial cells and the two male cells are markedly une- 

 qual. The pollen tube reaches the female gametophyte while 

 the latter is in the free nuclear stage. The archegonium 

 Initials appear almost immediately after free nuclear division 

 ceases. The nucleus of the central cell is fertilized, no ventral 

 nucleus being cut off. In the pro-embryo four free nuclei are 

 formed before walls appear. A mass of 12 to 18 cells is 

 formed and the pro-embryo passes the winter in this condition. 

 Suspensor formation is inaugurated the following spring by 

 the elongation of the tier of cells nearest the neck of the arche- 

 gonium/ followed by the successive elongation of other tiers. 

 The so-called „rumination" of the endosperm is caused by 

 irregulär encroachment of the endosperm on the perisperm. 

 The ruminated endosperm of the nutmeg and of Asimina trl- 

 loba was also examined and found to be caused in the same 

 way and not, as is currently reported, by encroachment of the 

 perisperm on the endosperm. About thirty months elapse 

 from the first appearance of the ovulate strobilus to the fall 

 of the seed. Charles J. Chamberlain (Chicago). 



Gatin, C. L., Sur la radicule embryonnaire du Miisa 

 Ensete Gmel. (Bull. Soc. bot. de Fr. T. LH. [1905.| No. 8. 

 p. 638—640. Avec fig.) 



L'^tude de l'embryon du Musa Ensete a fourni a Tauteur 

 un exemple interessant de point de v^g^tation de racine prin- 

 cipale de Monocotyledonee dans lequel l'ecorce et la coiffe 



