SUMMARY OF CURRENT RESEARCHES 



RELATING TO 



ZOOLOGY AND BOTANY 



(principally invertebrata and cryptogamia), 



MICROSCOPY, Etc.* 



ZOOLOGY. 



VEETEBRATA. 

 a. Embryolog-y.f 



Parental and Grand-parental Components of the Nucleus. J — 

 V. Hacker makes another important contribution to our knowledge of 

 the morphological aspect of inheritance. His chief results, apart from 

 theoretical deductions, may be summed up in four statements. 



(1) The " gonomeric " constitution of the nucleus, i.e. its composition 

 out of autonomous paternal and maternal contributions, may be followed 

 in the developmental history of Copepods from the fertilised ovum to 

 the primordial sex-cells of the offspring. 



(2) During the maturation of Cyclops there is a re-arrangement of 

 the chromatin-elements in such a way that the ovum acquires grand- 

 paternal and grand-maternal elements in equal mixture. With this 

 re-arrangement there is associated a pairing of each grand-paternal 

 chromosome with a grand-maternal chromosome. 



(3) It is highly probable that the " gonomeric " constitution of the 

 nucleus is of wide, if not general, occurrence in sexually reproduced 

 organisms, especially in genital and in epithelial cells. 



(4) There is a close connection between the idiomeric and the 

 gonomeric constitution of the nucleus, in this sense, that the latter may 

 be regarded as a limit-case of the former (cler letztere gcwissermassen als 

 ein Grenzfall des ersteren erscheint). 



But this brief report gives but a general hint of the drift of a 

 memoir which is as intricate as it is important. 



Maturation in Newts' Ova and in General.§ — W. Lubosch has 

 especially investigated the behavour of the nucleolar substance during 



* 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, Reproduction, and allied subjects. 



X Jenaische Zeitschr. f. Naturwiss., xxxvii. (1902) pp. 296-400 (4 pis. and 

 16 figs.). § Tom. cit., pp. 217-96 (5 pis.). 



