1895.] NATURAL SCIENCES OF PHILADELPHIA. 287 



THE JELLY-LIKE SECRETION OF THE FRUIT OF PELTANDRA 



UNDULATA Raf. 



* 



BY IDA A. KELLER. 



Having some time ago determined the origin of the thick coating 

 of jelly investing the younger parts of Brasenia peltata, Pursh, 1 I 

 was curious to seek the cause of a similiar secretion found in the 

 fruit of Peltandra undulata Raf., a plant widely separated from the 

 former so far as its natural relationship is concerned. 



The stage of development which first attracted my attention to 

 the voluminous secretion of this plant is represented in fig. 1, PI. 

 XII, where a, b, and e show three different views of the same plantlet. 

 Above may be seen the first leaf, I, thick, green and cotyledon-like. 

 Within this, and partly protruding beyond it, the second leaf, I. b. 

 The portion circumscribed by a rather wavy outline, /. is the jelly- 

 like mass in question. Roots are also beginning to emerge, as indi- 

 cated by r. 



The question naturally arose, from what portion of the fruit does 

 the jelly originate? Is it produced from special glandular organs as 

 in the case of Brasenia peltata Pursh, or is it the result of a meta- 

 morphosis of certain cells into this peculiar gelatinous mass without 

 the intervention of glands? Before proceeding to answer these 

 questions I will briefly outline the, anatomy of the fruit of this 

 plant. The fruit of the members of the Aracese family is, as we 

 are told, usually a berry. It appears to me, however, that the most 

 essential characteristic of this type of fruit, the well developed meso- 

 carp, enclosing the seed as a fleshy mass, is here conspicuously 

 reduced. The whole mass of tissue representing the pericarp, con- 

 sists of a few layers of cells, represented in fig. 2. It has the 

 appearance of a thin integument such as we find in a caryopsis or 

 utricle rather than that of a pulpy envelope. The material which I 

 had at command was, as a rule, one, or rarely two-seeded. Fig. 3 

 shows such a one-seeded fruit cut through lengthwise. The spheri- 

 cal embryo is represented by e. ; below e. is an empty space, v. Be- 



1 Proc. Acad. Nat. Sci., March 28, 1893. 



