ANATOMICAL NOMENCLATURE. 



127 



nearly circular. This part of the scapus I have termed the cochlear or 

 spoon (cch, Fig. 95). I believe that the scapus serves as an ovipositor, to 

 assist in the direction and arrangement of the eggs as they are extruded. 

 It has occurred to me to 

 inquire whether there 

 exists anj^ relation be- 

 tween the peculiar shape 

 of the scapus and the 

 character of the cocoon 

 laid by the female, es- 

 pecially in the position 

 and arrangement of the 

 eggs ; but I have reach- 

 ed no generalization on 

 this point. It is prob- 

 able that this organ al- 



ViEws OF Epigynum and Parts. 



Fig. 95. Lower part, that j^, the part next the ground when the spider is 



walking ; at, atriolura ; scp, scapus : cch, the cochlear or spoon of the 



scapus ; po, portulae ; gc, genital cleft. Fig. 96. Side view, to show the 



parra or buckler; other references as above. 



5(Cp 



Qd.sp 



so aids to clasp and direct the palpus of the male, or at least to regulate 

 the flow of the sperm, in the act of fertilization. 



In some species, as Epeira labyrinthea, Fig. 96, there is thrown up a 

 sort of wall in front of the scapus and on the anterior margin of the genital 

 cleft, which I liave termed the parmula, or simply the parm or buckler 

 (par. Fig. 96). In some species at least, as in Fig. 96, there appears a 

 groove or channel in the median part, indicating that this may also aid in 



directing the eggs during extrusion, or again in 

 guiding the inflow of the sperm. 



Underneath the vulval porch are (usually) 

 two concave openings or little gates, portuke 

 spermathecse (po), which receive the sperm from 

 tlie male palp, whence it flows from 

 Oviducts : gj^gi^ portula through a duct, aditus 

 Sperma- gpgj.,j^.^tliec£e (ad.sp), sometimes simple, 

 sometimes much coiavoluted; into the 

 spermathecffi (s.th). Thence another smaller 

 duct, the oviduct (ovd), admits the sperm to the 

 eggs (ov). The ovary also has an opening into 

 the portulfe, by which the eggs are discharged 

 when cocooning. The epigynum is subject to 

 immense variations in form, and these varia- 

 tions are nearly constant for every species; 

 hence they are good specific characters. I have not been able to find in 

 them any fixed generic value, although there is often a noticeable tend- 

 ency to a general likeness of form in any closely related group of species, i 



1 I hesitate somewhat to propose the above anatomical terms, as the field is one which 

 I have not specially cultivated. 



Fio. 97. View of epigynum in connection 

 with ovaries (partly diagrammatic) ; 

 atr, atriolum ; po, portulce ; scp, scap- 

 us; sp, cochlear or spoon ; ad.sp, aditus 

 spermathecse, sperm duct ; s.th, sper- 

 matheccE ; ov, the eggs ; ovd, oviduct. 



