1638.] 



Eeport on the Tea Plant of Upper Assam. 



363 



having been acquainted with the structure of the seeds of Camellia. In 

 the report of the Tea Committee published in the Journal of the Asiatic 

 Society for the year 1835, at p. 47, will be found an appendix containing 

 the marks, by which Dr. Wallich considers the two genera alluded to 

 to differ very widely. Before analysing the distinguishing marks, it will 

 be necessary to premise a few remarks on the structure of the fruit, by 

 which I mean the Ovarium in its mature state. A fruit, when simple, 

 consists of a single Carpellum, or modified leaf, rolled inwards, so that 

 the margins meet next (he axis : if it be completely normal, it consists of 

 a single cell. Most frequently, however, other Carpella enter into its 

 formation, and their margins being rolled inwards, it follows, that all wdll 

 meet at or near the axis. The inflected portions, if approximated, as is 

 usually the case, will divide such a fruit into as many cells, as there are 

 component Carpella, and the partitions or septa will necessarily be dou- 

 ble, although this cannot always be demonstrated. Of this structure is 

 the fruit of the Tea plant, consisting of three Carpella. 



Of the vertical dehiscence of such a fruit there are two principal modi- 

 fications. If it opens along the line of the inflected margins, each valve 

 will consist of the original Carpellum, now become distinct, the dissepi- 

 ments having divided into two plates forming the sides of each valve. 

 This modification constitutes the Septicidal dehiscence : it is likewise 

 expressed by some as consisting in the alternation of the valves with the 

 dissepiments, or in the valves having their margins turned inwairds. 

 But if the cohesion between the inflected portions be sufficiently strong, 

 (or perhaps from other causes) the dehiscence may take place along the 

 middle of the back of each cell or carpellum, usually indicated by a line 

 known to botanists by the term of dorsal suture : in this case the valves 

 are compound; and the partition will project along the middle of the 

 valve in the form of a keel. This is the loculicidal dehiscence, formerly 

 known by the phrase '* the dissepiments are opposite the valves." To 

 this modification belongs the dehiscence of the fruit of the Tea plant. 



It is now known that no higher value than that of generic importance 

 can be attached to such difference in the dehiscence of fruits. The 

 dehiscence is both in Thea and Camellia of the same nature ; 

 that is, loculicidal. Having reduced the dehiscence of the two fruits 

 to the same character, the question naturally arises, wdiere is the 

 wide difference? The only difference that does really exist, is simply of 

 specific value, consisting in the fruit of the Tea plant being three-lobed, 

 of the Camellia triangular. The question appears to me to be reduced to 

 this ; Dr. Wallich either intended to establish that the dehiscence of 

 the one is septicidal - of the other loculicidal, in which he has certainly 



