THE SPINNING ORGANS. 



45 



The immediate purpose of these anatomical studies was to throw liglit upon 

 the question, then much discussed, whether spiders actually possess the power 

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

 Can the 'pjjg question is considered elsewhere, although it is now hardly 

 pinner- ^yQj.j;}^y ^f g^ very serious discussion. As is often the case, both 

 Threads? Parties 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 atmosphere 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 rajjidity 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 sjiinning organs was sufficiently for- 

 midable to produce such a result. Independent 

 of tliis question, Mr. Meade's somewhat extended 

 studies, during which he compared the external 

 spinning organs of Orbweavcrs with those of other 

 tribes, have a real histological value, and I have 

 made use of some of his results, jjarticularly 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- 



FiG 37 Three glands . 



g, and the long tri- scctcd by him, thougli they differ greatly in form 

 articulate spinner- .^^^j number. As might be expected, they are 



et, sp, of Agalena x ' ./ 



labyriuthea. (After uiost highly dcvclopcd iu the wcb spmumg species, 



Underhill.) ^^^j^-j^ |^^ ^j^^^^^ ^j^.^^ j^^^^^^ f^^. ^.j^^-j. ^^^^^ ^ ^g ^j^^, 



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



J ) J . ■*■ ' ■*■ nmg 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 Tegraa'ria 



labyrinthica the silk glands are of a large tubular or clavate f^jj^^^u^jj^^.^' 



shaj^e (see Fig. 37), as is also the case in Tegenaria domestica. hin.) xi25. 

 (See Fig. 38.) 



III. 



This detailed description of the spinning glands may be appropriately 

 followed by a somewhat more detailed description of the organs through 

 which they discharge for the purpose of forming the silken lines of 



' I have supposed that all Lycosids practice ballooning ; but the subject is open for inquiry, 

 and it would be interesting if histology should point the way to a wider knowledge of natural 

 habit. 



\1 



