THE SPINNING ORGANS. 



45 



s - 



S P 



4 



The immediate purpose of these anatomical studies was to throw light 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 The question is considered elsewhere, although it is now hardly 



worthy of a very serious discussion. As is often the case, both 



p4-g T33,T*Tt 



Threads? P ar ^ es 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 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 

 hi all species of British and foreign spiders dis- 



FIG. 37. Three glands, i i , 



g, and the long tri- sected by him, though they differ greatly in form 

 articulate spinner- and num b er . As might be expected, they are 



et, sp, of Agalena 



labyrinthea. (After most highly developed in the web spinning species, 

 while in those that hunt for their prey, as the 

 Lycosids, they are few and small in comparison, with the excep- FlG - ** Spin ~ 



. ning gland, 



tion of those species which are aeronautic in their young state. 1 g; duct, d ; 

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



labyrinthica the silk glands are of a large tubular or clavate 



, ' T-T rt-\ T i m (AfterUnder- 



shape (see fig. St), as is also the case in legenaria domestics, hiii.) 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 



1 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. 



