THE MUSEUM. 



171 



•etc. , with which the pitcher was more 

 or less choked. 



Although many spiders of semi- 

 aquatic habits, such as Dolomedes, 

 Thalassius, and some species of Lyco- 

 sida, plunge beneath the surface of 

 water when threatened with danger, 

 and escape along the stems of the 

 subaqueous weeds; and although an 

 example of Araneus ;Epeira cornutu?. 

 a terrestrial species, which, however, 

 frequents the banks of streams and 

 marshy country, has been noticed, 

 when disturbed, to drop to the ground, 

 run into the water, hide beneath a 

 tuft of weed, and there remain a min- 

 ute or so before venturing to climb 

 back to its web, I am not aware that 

 the adoption of water as a city of 

 refuge has ever been recorded of any 

 member of the family Thomisidit. 

 These spiders, in fact, as already ex- 

 plained, depend for safety upon pro- 

 tective assimilation to their surround- 

 ings. Consequently, the habit of 

 plunging into the fluid in the pitcher 

 of Nepenthes, adopted by Misumena 

 nepenthicola, must be regarded, it 

 appears, as a new instinct acquired by 

 the species in connection with the ex- 

 ceptional nature of its habitat; and its 

 behavior carries with it the conviction 

 that the species is constantly subject 

 to persecution from some enemy other 

 than man, whether it be bird or wasp. 



Possibly the spiders, when once 

 they have taken up their abode in the 

 pitcher are, like the insects that ven- 

 ture in, unable to get out again on ac- 

 count of the opposition to exit offered 

 by the slipperiness of the walls of the 

 conductive area. If this be so, they 

 would be compelled, in case ot attack, 

 to seek safety in the lower parts of the 

 pitcher; and while those too timid to 

 take the plunge, or too weak to with- 

 stand the immersion, would be cap- 

 tured or destroyed, their instinctively 

 bolder or physically hardier compan- 

 ions would be saved to transmit their 

 characteristics; and so by a process of 

 elimination and selection the instinct 

 would be irradually brought to the 



state or perfection Mr. Everett has 

 described. 



Lastly, if it be wondered by what 

 means the spider is able to resist the 

 tliiid, and to regain its position of se- 

 curity in the upper part of the pitcher, 

 it must be rememberetl, in the first 

 place, that a great many spiders, as 

 well as many insects, can be immersed 

 in water and other liquids and with- 

 drawn in a perfectly dry state; and in 

 the second place, that almost all 

 spiders, when dropping from their 

 webs or leaping after prey, insure a 

 safe return to the spot they have left 

 by letting out a drag-line of silk, which 

 passes from the spinning mammilhe to 

 the point of departure. A silken 

 thread of this description would enable 

 M. nepenthicola to climb out of the 

 digestive tluid which retains the cap- 

 tured insects; while the nature of the 

 integument and of its hairy clothing 

 would prevent the penetration of the 

 fluid during the short time that the 

 spider remains beneath it. — A'. /. Po- 

 cock\ ill Xaturc. 



Shell Collectors. 



We trust that Conchologists will not 

 overlook the fact that ////(• s/n-//s are now 

 our specialty. We are constantly ac- 

 quiring new and desirable things and 

 have several thousand good species in 

 stock. Nearly every family of shells is 

 represented by numerous examples. 

 If you specialize any particular group 

 send for written list of what we have 

 that will interest you. Our stock of 

 Minerals, Corals, Eggs, Skins, Land 

 and Marine Curios is for sale at a sacri- 

 fice. .\ny collector wishing to start as 

 a dealer can here find a desirable bar- 

 gain at prices much below what thej' 

 could be secured for elsewhere. Write 



us. 



WALTER F. WEBB, Mgr., 



Albion, N. Y. 



