+ 



for the benefit of such of our readers as are interested in 

 microscopical inquiries. 



Dr. Brown considers the position of the respiratory 

 pores or stomata, their form, and relative size with respect 

 to the areolations of the cuticle, to be often points of much 

 value in determining the limits and affinity of genera, and 

 even of their natural subdivisions. In the genus Banksia, 

 he says, " There are no cutaneous glands" (meaning 

 breathing pores) " on the upper surface of the leaves; 

 those of the lower surface are oval, sometimes broader 

 than long, with an annular simple limb, and a linear disc ; 

 they are always concealed by a sort of curly wool ; when 

 the leaves are veinless, or furnished with anastomosing 

 veins, they are scattered pretty equally over the cuticle; 

 but more frequently, when the veins of the leaves are 

 reticulated, they are clustered in the bottom of the hollows 

 between the veins. Hollows of a similar nature, and with 

 precisely the same arrangement of clustered glands (stomata) 

 in their bottom, exist in Nerium Oleander and odorum: these 

 hollows were formerly well represented in the N. Oleander 

 by Malpighi, and more recently by Krocker; both these 

 authors considering them pores or clefts of unusual size 

 and form. More recently they have been considered 

 M. Adolplie Brongniart as perforations in the outer layer 

 of a double epidermis, the inner layer of which (in the 

 bottom of the hollow) this author describes as destitute of 

 glands." 



To these curious observations, the accuracy of which we 

 have ourselves verified, is prefixed the following explana- 

 tion of the anomalous structure of the fruit of Banksia. 

 Every body who has ever opened a cone of a Banksia 

 knows that the two seeds which are contained in each 

 cavity are separated by a loose partition ; and Botanists 

 are aware that the origin of that partition is a problem 

 which had never been solved till Dr. Brown undertook it in 

 the appendix to Captain King's Voyage. The explanation 

 given of it is contained in the following description : — "The 

 ovarium is one-celled, with two ovules. These ovules are 

 collateral, and attached by their edge above the middle; 

 their skin has on the outer side a longitudinal open cleft, 

 in consequence of which the principal part of the inner 

 membrane, which encloses the nucleus, is laid bare. Soon 



