1888.] NATURAL SCIENCES OF PHILADELPHIA, 11 



the seed it forms a few leaves which differ widely from those which 

 appear on the same plant a little later. The adult stage of these 

 first leaves is from a twentieth to a tenth smaller than the adult 

 stage of the second or later developed leaves. Generally only from 

 five to ten of these first-leaves are produced. 



After the second leaves begin to appear, then no more of the first 

 form are grown by the plant. 



In the ordinary leaves of S. purpurea it is well known that the 

 hood surmounting the hollow leaf is erect and in no wise protects 

 or covers its opening. In S. variolaris this is just the opposite — 

 here the hood, a little above and back of the opening, makes a 

 sharp bend forward and not only covers over the whole orifice but 

 projects beyond it on all sides nearly 2 inch. 



These first or seedling leaves oi' S. purpurea reseirfble in form not 

 the later and adult leaves on the same plant, but those of /S. vario- 

 laris. The hood is not erect but arches over the hollow leaf in pre- 

 cisely the same manner as in the adult leaves of ;iS. variolaris. 



There are also two forms of leaves in ^S'. variolaru. In this plant, 

 however, the difi^erences are not so much a matter of shape as appar- 

 ently of arrested development. The first leaves are very much like 

 the adult form on the same plant only being from ten to twenty 

 times smaller. 



But the important fact remains to be stated : — ^the first leaves from 

 each of these plants are perfect miniatures of each other. It would 

 be next to impossible for an expert to separate them, should they 

 happen to become mixed, and to accurately say which belonged to 

 the one or which to the other of the two species. 



The production of this first set of leaves by S. purpurea which so 

 very closely resemble the ordinary leaves of S. variolaris had led him 

 to believe that the species pu?'pwrea Ls a retrograde development from 

 variolaris. 



Misbelief in this is, however, not wholly based on the production of 

 the early leaves, but rests upon several other important facts. 



8. variolaris is a very highly specialized plant for the purpose of 

 catching and digesting insects. Up and down the margin of the 

 wing and around the mouth of the protected pitcher are numerous 

 honey glands. In the interior is the smooth surface and also the 

 hairy ones to prevent the escape of insects which have fed up to the 

 top of the leaf and then fallen into this treacherous opening. These 

 special adaptations are all present in >S'. purpurea, but the honey 

 glands seldom secrete any nectar and are sometimes even rudi- 

 mentary. Again the fluid found in S. variolaris contains a consider- 

 able quantity of a digestive ferment which acts directly upon the 

 entrapped insects. This is not so in the fluid excreted by the leaves of 

 S. purpurea. Only a trace of this ferment could be found after the 

 most careful chemical search for it. 



