26 



HARDWICKE'S SCIENCE-GOSSIP. 



[Feb. 1, 1868. 



singular plants is the Venus's Ely Trap (Dionaa 

 muscipida), whose broad flat leaves, studded with 

 stiff hairs, close suddenly together as soon as any 

 small insect alights on them, and clasps the wretched 

 victim in an embrace of death ; for it is only when 

 the little prisoner has ceased to struggle for its 

 freedom, that the two surfaces begin to relax their 

 grasp, and return to their former position. 



There is a remarkable fact connected with all 

 these mysterious movements — viz. that they depend 

 in a great measure on climate and temperature — not 

 altogether for their existence, but certainly for the 

 feebleness or activity which they display. Thus, in 

 the hottest parts of the tropics, masses of Mimosa 

 pudica fall prostrate before the advancing foot of 

 the traveller ; the sensitiveness with which the 

 plants are endowed being communicated from one 

 to the other faster than an ordinary person can walk. 

 But let the same plant be transported to an English 

 greenhouse, where it vegetates and nothing more, 

 and it will barely acknowledge the contact of the 

 hand by the drooping of its leaflets. 



Again, we are told by a recent traveller (Dr. 

 Jameson) that there is a small gentian (67. sedifolia) 

 to be found on the lofty plains of Peru, which at 

 15,000 feet above the sea level is gifted with a 

 peculiar sensitiveness to touch — a quality almost 

 entirely wanting in specimens growing at a lower 

 level. 



What then are we to say to these instances ? Are 

 we to suppose that plants are endowed with some 

 kind of perception ? Or are we still to retain the 

 old distinction, which assigns sensation to animals, 

 and Irritability (whatever that may mean) to plants ? 



W. W. Spicer. 



HAIR OE INDIAN BATS.* 



T710R five-and-twenty years an object has been 

 -■- known to microscopical observers as the 

 "hair of Indian Bat," and during that period, if 

 efforts have been made to discover its source, those 

 efforts have" not been crowned with success ; for 

 it is still unknown what species of bat yields the 

 hairs which are employed as test objects. Bull 

 of hope that this species might be discovered, the 

 investigations which led to the production of this 

 paper were undertaken. Eacilities occurred for 

 examining the hairs of a large number of well 

 authenticated species of Indian Cheiroptera, and 

 the result of this examination forms the subject of 

 the present communication. 



The first observer who appears to have paid any 

 special attention to Bat Hair, or at least the first 

 who made any mention of the hair of Indian Bat, 

 was Mr. John Quekctt in a paper read before the 



* Abstract of a paper read by Mr. M. C. Cooke at the 

 Quekett Microscopical Club, January 24, 1868. 



Microscopical Society of London on the 20th of 

 October, 1S11, and printed in the first volume of 

 the Society's Transactions (page 5S). Towards the 

 close of this paper its author observes—" Since 

 these observations were made I have been kindly 

 favoured by Mr. Powell with some hair of a bat 

 from India, the species of which is at present un- 

 known. The scales are most remarkably developed, 

 and in some of the hairs they surround the shaft 

 in a continuous whorl, and, without any preparation 

 by scraping, in many places they will be found to 

 be entirely wanting, whilst in others they are still 

 attached to the shaft, but out of their proper 

 position." This "paper is accompanied by a plate 

 iu which the best figure of the Bat-hair in question 

 is given which has hitherto been published. In his 

 "Treatise on the Microscope," Quekett gives another 

 and different figure of the same kind of hair, but 

 much less accurate. In the latter instance the 

 scales are represented as a series of whorls of linear 

 scales, or at least so deeply cut as to have that 

 appearance, an arrangement which is exceedingly 

 doubtful either in Bat-hair or that of any other 

 known animal which has hitherto been examined. 



Dr. Carpenter, in his excellent work on the 

 microscope, alludes to the hair of this Indian Bat in 

 the following words, " it has a set of whorls of long 

 narrow leaflets (so to speak) arranged at regular 

 intervals on its stem" (pp. 644, fig. 329c, 1857). 

 The authors of the " Micrographical Dictionary " 

 appear to bold the same opinion of its structure. 

 Dr. Hogg in his figure exhibits Dr. Carpenter's 

 theory, and in his remarks quotes Quekett. In 

 Griffith's "Text-Book for the Microscope," the 

 author writes — "in the hairs of some of the foreign 

 Bats the scales are whorled, forming very beautiful 

 objects." In Willkomm's " Die Wunder des Mikro- 

 skops," the figures of which are singularly enough 

 identical with those iu " Hogg on the Microscope," 

 the hair of the Indian Bat is given without special 

 remark. As one of the "curiosities of micro- 

 scopical literature," it may be remarked that the 

 figure given in Eonvielle's "Les Merveilles du 

 Monde Invisible " as the " hair of a bat " is that of 

 the larva of Antlirenus. 



The most satisfactory account, because the most 

 correct and explicit, is that given by Mr. P. H- 

 Gosse in his "Evenings with the Microscope." 

 Writing of the hair of a species of Bat from India, 

 he states, " the trumpet-like cups are here very thin 

 and transparent, but very expansive ; the diameter 

 of the lip being, in some parts of the hair, fully 

 thrice as great as that of the stem itself. The 

 margin of each cup appears to be undivided, but 

 very irregularly notched and cut. In the middle 

 portion of the hair the cups are far more crowded 

 than in the basal part, more brush-like, and less 

 elegant, and this structure is continued to the very 

 extremity, which is not drawn out to so attenuated 



