34 



AMERICAN SPIDKRS AND THEIR SPINNINGWOKK. 



the differences. He calls attention to the fact that Cteniza's door consists 

 of a series of superimposed layers of silk and mud, amounting sometimes 

 to thirty, 1 is thick, of equal width, and beveled at the edge ; while Opifex 

 makes a thin door composed of a single layer of silk and soil, much thicker 

 in front, and with unbeveled edge. The hinge of the former is also tough 

 and elastic, while the latter is feeble and with little elasticity. All this is 

 true, but Mr. Wagner appears to have lost sight of the fact that the Ter- 

 ritelarise embrace many species besides Nemesia and Cteniza whose indus- 

 try is greatly varied in form, and furnishes examples much nearer that of 

 Wagner's species than the one with which he compares it. Moggridge has 

 called attention to these in that form of trapdoor which he calls the 

 "wafer" type as distinguished from the "cork" type. 2 The latter is the 

 form with which alone Mr. Wagner appears to have been familiar, while 

 the former more closely resembles his own interesting discovery. 



The eminent French araneologist, M. Eugene Simon, has added greatly 

 to our knowledge of these aranead architects, and I have quoted freely 3 



COMPARATIVE VIEW op LYCOSID ARCHITECTURE. 



FIG. 28. Lycosa scutulata, simple burrow in the ground ; a temporary closure for moulting and cocoon- 

 ing. FIG. 29. Funnel shaped tube of silk, more or less supported and disguised by vegetable foliage and 

 debris ; Lycosa tigrina. FIG. 30. Turret of silk protected by armor of twigs or grass bits ; Lycosa arenicola. 

 FIG. 31. Vestibule of silk, armored with moss, etc., with a rude door, Lycosa tigrina. FIG. 32. Silk lined 

 burrow, with wafer trapdoor at surface; Tarentula opifex. 



from his papers and given a number of illustrations exhibiting the appar- 

 ent development of this peculiar industry, from the mere straight burrow 

 to the beautiful silk lined tube of Cteniza, crowned with its admirable 

 hinged trapdoor. In this series is one, the nest of Stothis astuta, 4 a South 

 American species, which in its general characteristics resembles that of 

 Wagner's Basketlid spider. The same wafer door is found upon the nest 

 of another species, Dolichoscaptus Latastei Simon, which builds a columnar 

 turret covered with a movable lid. 5 We are thus able to construct a double 

 comparative series of nests, one from the Lycosids, the other from the Ter- 

 ritelariffi, which will show the following facts : First, a progressive advance- 

 ment from the simple tubular burrow in the ground to a silken lined bur- 

 row covered by a hinged lid. Second, the various stages of the two series 



1 Bee Vol. II. of this work, page 249 and Fig. L'lil. 



2 " Harvesting Ants and Trapdoor Spiders." 

 * See Vol. II. of his work, page 409, sq. 



4 Vol. II., page 412, Figs. 347-349. 



5 Vol. II., page 411, Fig. 346. 



