121 



AMERICAN SPIDERS AND THEIR SPINNINGWORK. 



Deduc- 

 tions. 



matter of those tissues which are atrophied and undergo the regenera- 

 tion of the fat benefits the organism in three ways : First, in transmitting 

 that matter by means of the amoeboid blood cells, which assim- 

 ilate and plasmatically digest it, 1 essentially after the regeneration 

 of grease becomes less intense, and even appears to have touched 

 its limit. Second, in transmitting the matter by means of the red blood cells 

 which assimilate it by absorption. Third, by means of globules of grease, 

 which in themselves present certain forms whose role is to transport the 

 nutritive matter into the whole body. 3. It is doubtful whether, without 

 cooperation of blood cells, regeneration of fatty tissues would proceed to 

 complete disappearance ; if it could occur it would be after a considerable 

 and indefinite time. 4. The process of degeneration of muscular tissue in 

 spiders, in its general traits, suggests that of vertebrate animals. 



es 



VI. 



In the descriptive matter to which the second part of this volume is 

 devoted certain terms and abbreviations are used that require explanation 

 y JVIR and illustration, which it seems best to 



Nomen- i nser t together at this point for con- 

 catureo ven j ence O f re f erence . The quadrilat- 

 tion era l described by the middle group of 



four eyes (MF and MR) is called the 

 ocular quadrilateral, or more commonly " ocular 

 quad " (Fig. 87, oc.q), as at once a brief and 

 definitive term. The ocular area or eye space 

 FIG. ST. Face of orbweaver ; ciy, (es) is that part of the face over which the eight 

 ciypeus; es, eye space; MF, MR, e y es are distributed. The curvature of the eye 



midfront aud midrear eyes ; SF, . . . . - 



SR, sidefront and siderear eyes; rows forms an important characteristic in deter- 

 oc. q , ocular quad; v, vertex. mining species. The rows are said to be pro- 

 curved when the concavity is directed forward toward the mandibles, and 

 recurved when the concavity is directed backward. When the row is 

 straight, or nearly so, it is said to be " aligned," or nearly so. In deter- 

 mining the curvature the 

 ' eye rows have been looked 

 at from the front, and a little be- 

 low the horizon of the front row. 



The Byes. 



Fid. 88. 



FIG. 89. 

 CURVATURE OF EYES. 



Fill. 90. 



It is often difficult to determine the 



PYflrt OlirvahirP PSTlPf-iflllv fl<? it dif FlC " W - Front row recurved, rear row procurved. FIG. 89. 

 re, CSpei Both rows p rocurve d. FIG. 90. Front row nearly aligned, 



CrS With the point Of Vision. In slightly recurved, rea^row procurved. 



Fig. 88 the front row of eyes is recurved, the rear row slightly procurved ; 

 in Fig. 89 the front as well as the rear row is procurved ; in Fig. 90 the 

 front row is nearly aligned, the rear procurved. 



1 See Wagner, " Du Sang des Araigiu'es." 



