— 110 — 



A few furtliei- poculiarilies in M acfu il ;i lie's new hook must 

 be mentioned. In N. hicalcarata the collar, as it is well known, 

 bears, near the jiiace where it is connected with the lid, two long 

 spines, turning their points against the cavity of the pitcher. Tiie 

 utility of these has been explained in several odd fashions, one of 

 which in a renovated form appears in (13): "Burbidge's ex- 

 planation of their significance seems good. He observed in North 

 Borneo that tlie pitchers of many species are visited by the small 

 rodent Tarsius spectrum. Perched on the pitcher margin, it bends 

 in its head and neck, scoops out the caught insects and devours 

 them. But if it attempts such action witli N. hicalcarata the two 

 sharp spines often transfix it by the nape of the neck, and tumble 

 it into the pitcher, or frighten it from attempting such action on 

 other pitchers of the species. Another suggested explanation of 

 the spines has recently been made, by supposing that they exude 

 honey drops by their tips from a few marginal glands that are so 

 placed as to cause an insect that attempts to sip, to drop off 

 into the pitcher cavity. Such may be a partial reason for their 

 gradual evolutionary selection and development, but Burbidge's 

 view seems more natural" (pag. 10). 



Dr. Mac far lane does not seem very particular in choosing 

 his explanations. Also in the following remark the author shows 

 a more than ordinary confidence in the power of the natural 

 selection: "That these alluring nectar glands should wholly or 

 mainly be confined to the lower laminar surface is appropriate 

 and explicable on principles of natural selection, when one remem- 

 bers that insects in the tropics usually run along that area, and 

 so sheltei themselves from the observation of enemies" (pag. 17). 



Such explanations do not, in the slightest degree, contribute 

 to clear up the causes of the said phenomena, and this tendency 

 to regard "Natural Selection" as an explanation of all difficult 

 problems was, as far as I know, foreign to Darwin's train of ideas. 



II. Epidermal Formations on the Corrugated Rim. 



The corrugated surface of the collar is of a special interest. 

 Besides the great corrugations, which as well on the outer as on 

 the inner border of the collar are pointed, and of which Faivre 

 says that they are "placés comme à cheval sur la paroi de l'urne", 

 there runs over each row of epidermal cells, along the large ones, a 



