386 Morphologie, Teratologie, Befruchtung, Cytologie. 



up to the stage with four nuclei. The next divisions are confined 

 to the antipodal region, where the two original nuclei, by subse- 

 quent divisions, give rise to a group of large free nuclei, usually 

 twelve in number. The two mycropylar nuclei divide once, and 

 there is formed a typical egg apparatus and an Upper polar nucleus. 

 The antipodal nuclei divide further; cell-walls are formed, and the 

 number of antipodal cells may finally exceed sixty-four. A varying 

 number of the antipodal nuclei become free and assume the röle of 

 polar nuclei, fusing with the Upper polar nucleus into a Single large 

 endosperm nucleus. Sometimes the fusion results in two primary 

 endosperm nuclei. Agnes Arber (Cambridge). 



Gibbs, L. S., On the Development ot the Female Strobilus 

 in Podocarpus. (Ann. Bot. XXVI. p. 515—571. pl. 49—52. 1912.) 



In the course of travels in New Zealand, Fiji and North 

 Borneo, the author collected material of the female strobilus of 

 thirteen species of Podocarpus. Upon this material, a thorough 

 re-eximination of the cones and ovules of this genus has been 

 based. The author points out that accepted morphological ideas upon 

 this group of conifers are based almost entirely upon the study of 

 dried material, and shows that these ideas need modification in the 

 light of field work. 



The conclusion drawn \>y the author is that this study strikingly 

 reveals the relationship of the fruiting axis of Podocarpus to the 

 cone of the Abietineae and its component parts, a relationship pre- 

 viously suggested by Bennett and Brown, Sperk, Bertrand 

 and Tison. According to this view, the "aril" or "epimatium" in 

 Podocarpus corresponds to the "ovuliferous scale" of the other Conifers. 

 It is shown that, in Podocarpus, as the ovuliferous scale becomes 

 more important and independent, the fruiting axis gradually loses 

 its strobiloid Organisation. Agnes Arber (Cambridge). 



Lawson, A. A„ The Phase of the Nucleus known as Syn- 

 apsis. (Trans. Rov. Soc. Edinb. XLVII. p. 591-604. pl. 1—2. 

 1911.) 



The author discusses the numerous records in the literature ol 

 the stage known as "Synapsis", which immediately precedes the hete- 

 rotype mitosis, and concludes that it is a constant and normal phase 

 in the nuclear cycle. He offers, however, an entirely new interpre- 

 tation of meaning of this phase. He illustrates his views by obser- 

 vations on Smilacina, but points out that all the main conclusions, 

 arrived at by a stud} 7 of this plant, were later confirmed by an 

 investigation ot types from the Gymnosperms, Pteridophyta, 

 Bryophyta and Algae. The view which he puts forward may be 

 summarised as follows: 



Spore-mother-cells, being both storage and meristematic in 

 their function, present an Organisation that is strikingly different 

 from that found in ordinary vegetative tissue. Being charged with 

 food substances for the production and sustenance of four spores, 

 they are devoid of vacuoles of any measurable size in the cytoplasm. 

 During their development, however, there is a great accumulation 

 of sap within the nuclear cavity, which causes a great osmotic pres- 

 sure, in the same manner that cell-sap does in the vacuole of gro- 

 wing vegetative cells. The pressure, acting from within, causes the 



