TRANSACTIONS OF SECTION D. — DEPT. ZOOLOGY AND BOTANY. 375 



tip. A short cirrus of four or five segments extends from the extremity of the 

 dorsal margin, while beneath it is a dense tuft of long straight sword-shaped trans- 

 lucent bristles, similar to those described in the female bud. A flat papilla, about 

 the middle of the bristle-bundle, shows that part of the foot to which the tip of the 

 slender supporting spine proceeds. This slender spine diverges upward from the 

 side of the stronger inferior one, the arrangement of the parts indicating that the 

 foregoing tuft of simple bristles is of less morphological value than the others. A 

 somewhat lanceolate process occurs at the ventral margin of the foot, and apparently 

 corresponds to the setigerous division. It is supported by the stronger spine, and 

 bears two or three bristles, with simple terminal processes, similar to those in the 

 parent-stock. No ventral cirrus is present. The body contains a large number of 

 granules, and also masses of what appear to have been fully-formed spermatozoa. 

 Whether this is the male of the above form or another is, of course, an open ques- 

 tion ; but the bristles certainly correspond. 



SA TURD A Y, A UG UST 23. 



The Department did not meet. 



MONDAY, AUGUST 25. 



The following Papers were read : — 



1. Recent Additions to the Moss-Flora of the West Riding. 

 By Charles P. Hobkirk, F.L.S. 



This paper is supplementary to one read by the author at the Bradford Meeting 

 in 1873, ' On the Mosses of the West Riding,' giving a list of 294 species, with 

 their localities. After treating on the work of the Yorkshire Naturalists' Union, 

 in investigating the fauna and flora of the county, the author particularised some 

 of the chief species found since 1873, and gave the history of them, viz., Seligeria 

 trhtieha at Littondale ; Aulacomnium turgidum at Whernside ; Fontinalis gracilis 

 at Malham Cove ; Plagiothecium nitidulum at Penyghent, &c. Four lists were 

 appended to the paper, viz., (1) New species, 48; (2) Species found in fresh 

 localities, 142 ; (3) Localities previously known, but not recorded, 29 ; and (4) 

 Species inserted in error in previous list, 8 : making the total number of species now 

 recorded for the Riding, 327. 



'2. On the Embryology of Gymnadina conopsea. By H. Marshall Ward. 



The ovule arises on the placenta as a mass of cells consisting of an axial row, 

 surrounded by an epidermal layer of cells one deep : the terminal cell of the axial 

 row, just beneath the epidermal layer, enlarges and cuts off two cells at its apex 

 as described by Strasburgher ; these cap-cells and the epidermal cells become flat- 

 tened and finally destroyed as the cell which remains enlarges and becomes the 

 embryo sac. The existence of the remains of the cap-cells as refractive masses 

 above the embryo sac is cited as evidence against Vesque's view as to the origin 

 of the embryo sac by the fusion of two or more superposed cells. The protoplasm 

 in the embryo sac then divides into two masses, one passing to each end of the 

 sac ; they there undergo further division into fours. Of the four nucleated masses 



