Minutes of Proceedings. vii 



Eevista del Museo de La Plata, VI., 2. 



Eecords of the Geological Survey of New South Wales, Vol. IV., 

 Part 4. 



Select Extra-Tropical Plants, &c, by Baron F. von Mueller. 



Bulletin de l'Academie Imperiale des Sciences de St. Petersbourg, 

 II., 5; III., 1. 



Memorias y Eevista de la Sociedad Cientifica, ' Antonio Alzate,' 

 VIIL, 1, 2. 



Sitzungberichte der Kaiserlichen Akademie der Wissenschaften, 

 CIII., 4 and 5, 6 and 7, 8-10. 



It was moved by Dr. J. A. Eoss, and seconded by the Eev. 

 G. H. E. Fisk : 



"That the Council of the South African Philosophical Society be 

 requested to take into consideration whether it is advisable to bring 

 before the notice of the Government the desirability of encouraging 

 scientific research by admitting instruments for that purpose free of 

 duty, and if so to take steps accordingly." 



Dr. F. Puecell read some notes on the structure and development 

 of the eyes of certain arachnids. He stated that the eyes of arach- 

 nids belong to one or other of two types, according as the cells or 

 the retina are inverted or not. The eyes of the Phalangiidce, or 

 Harvest-men, belonging to the inverted type, were described in 

 detail. In this family the cells of the retina are arranged in 

 characteristic groups of four cells each, one central being surrounded 

 by three peripheral ones. Each cell secretes at its distal end a 

 hyaline visual rod, assumed to be the sensitive portion of the cell. 

 The four rods of each group of cells are fused to a single piece of 

 complicated structure called the rhabdome. Their outer ends only 

 are exposed to the light which enters the eye through the lens, 

 while the rest of their surface is cased in black pigment. When, 

 however, the animal is kept in a very dimly lighted place for some 

 hours, the pigment changes its position, so as to leave a large portion 

 of the rhabdome exposed to the light. Some reference was made to 

 the phylogenetic origin of the eye. 



An interesting discussion followed upon the evolution of the 

 different types of eyes, in which Messrs. Fuller, Eaffray, Stone y, 

 Coestoephine, and the Chaieman took part. 



