THE 8PIXNIXG ORGANS. 



45 



S-- 



The immediate purpose of these anatomical studies was to throw liglit ui)on 

 the question, then mucli discussed, wliether spiders actually possess the power 

 of shooting out threads to a greater or less distance into the air. 

 Can the q^j^g question is considered elsewhere, although it is now hardly 

 Spinner- ^^.Q^.^j^y Qf j^ y^py serious discussion. As is often the case, both 

 Threads? P^^i'^i^s were right though they appeared to be at oppo- 

 site poles of the subject. In other words, spiders do not 

 possess the power of darting threads into the air to any consid- 

 erable distance, and are dependent upon the atmosi)here to elevate 

 those lines upon which they ascend, and those which they ex- 

 trude for web foundations. But in the act of swathing insects^ 

 and on other occasions also, it is possible for the aranead to 

 expel liquid silk with great rapidity and violence, 

 and at least for a short distance. This I have 

 often observed. Mr. Meade abundantly demon- 

 strated that the muscular apparatus furnished to 

 the internal spinning organs was sufficiently for- 

 midable to produce such a result. Independent 

 of this question, Mr. Meade's somewhat extended 

 studies, during which he compared the external 

 spinning organs of Orbweavers with those of other 

 tribes, have a real histological value, and I have 

 made use of some of his results, particularly for 

 comparison with the more perfect work of others. 

 According to Mr. Meade, the nature and con- 

 struction of the silk glands are essentially the same 

 in all species of British and foreign spiders dis- 

 g, and the long tri- scctcd by him, tliougli they differ greatly in form §] 

 articulate spinner- ^^^-^j numbcr. As might bc exiiected, they are 



, et, sp, of Agalena , , • i i i i i • -i 1 • • • 



labyrinthea. (After UlOSt highly dCVClopcd 111 tilC WCU Spmillllg SpCClCS, 



underhiii.) while ill those that hunt for their prey, as the 



Lycosids, they are few and small in comparison, with the excep- ^"^- ^- f p'"' 



•I'd ... ning gland, 



tion of those species which are aeronautic in their young state. ^ g; duct, d; 

 They appear to be similar in the males and females. In Agalena of xegenaVia 

 labyrinthica the silk glands are of a large tubular or clavate domestica. 



'' ^ ... (Afterllnder- 



shape (see Fig. 37), as is also the case in Tegenaria domestica. hui.) xi25. 

 (See Fig. 38.) 



III. 



This detailed description of the spinning glands may be appropriately 

 followed by a somewhat more detailed descrii>tion of tlie organs through 

 whicli tliey discharge for the purpose of forming the silken lines of 



^ I have supposed that all Lycosids practice balloonin<r; but the subject is open for inquiry, 

 and it \v<iul(l he interesting if histology should i)oint tiic way to a widiT knowledge of natural 

 hal)it. 



