904 RECORD OF CURRENT RESEARCHES RELATING TO 



motlici'-coll does or does not exliibit an aj^ical increase during the 

 formation of the walls. 



The groups of Fluviales, Eanunculaceae, and Cruciferae present 

 two special mother-cells ; three have been observed in the greater 

 part of Mouocotyledones and Apopetalae ; four or five in Gamopetalae, 

 Santalacefe, Aristolochiacese, &g. 



The observations of the author lead him to apply the term 

 embryo-sac to the collection of cells which proceeds from the 

 primordial mother-cell. 



In certain Liliaccfe, such as Lilium, each of the special mother- 

 cells produces, by the division of its nucleus, a tetrad of nuclei which 

 are the homologues of pollen-grains and of macrospores. The 

 septum which separates the first and second cells becomes resorbed 

 before the division into tetrads commences. The single cavity which 

 results (the embryo-sac properly so called) finally encloses eight free 

 nuclei which behave in the way that Strasburger has described. 

 In the remaining Liliaceae, Agraphis, Muscari, &c., the first and 

 second cells alone give birth to four nuclei, while the lower special 

 mother-cells produce an apparatus to which M. Vesque has given the 

 name anticline. In Lachenalia, on the contrary, the first cell alone 

 gives rise to a tetrad ; three of its nuclei form the sexual apparatus ; 

 the fourth unites itself with the undivided nucleus of the second cell 

 and coalesces with it. 



The Amaryllidaccfe, Iridacefe, Aroidea), Juncaccfe, Cyperaceae, &c., 

 differ but little from the common type of Liliacea3, which occurs 

 again very commonly in the Apopetalfe, as in the Euiihorbiacete, 

 Papaveraceas, Eosacea?, and allied families. 



The exception presented by Mouocotyledones, among which the 

 presence of a single tetrad has been established, occurs frequently 

 among Apopetalpe — in Saxifragacea3, Onagrariacefe, &c. — and becomes, 

 so to speak, the rule among Gamopetala3 ; while Caprifoliaceje and 

 Valerianacefe do not present this character, and thus offer a greater 

 resemblance to ordinary Apopetalfe. The first cell always produces 

 a complete tetrad, even in the most highly organized Gamopetalfe, 

 such as Com2)ositPe. 



The cells to which the author gives the name of anticlinal present 

 remarkable differences in their development. Sometimes they are 

 arrested immediately after their development (ine^-t anticlinals) ; some- 

 times they increase and divide after impregnation, and thus produce 

 the albumen (active or albuminigenous anticlinals), as in EricaceaB, 

 Scroi)hulariacefe, Labiatte, &c. ; sometimes again they elongate and 

 ramify in order to reach, in the tissues of the chalaza or even of the 

 placenta, as in Osyris, &c., the nutritive substances which they bring 

 to the other anticlinals to enable them to divide (cotyloid anticlinals). 

 The part which the development of the albumen takes in the pro- 

 duction of the special mother-cells suggests a comj)arison with the 

 prothallium of Vascular Cryptogams. This remark applies also to the 

 albumen which is formed in the first and second cells by the division 

 of the central nucleus, whether the multiplication of the nuclei bo 

 accompanied by the simultaneous formation of septa, as in Plantagi- 



