/ _ 



2 Anudls Eiitonioloi'U'dl Society of Anicrini \\()\. Ill, 



bear distinctive names, I propose that this term be restricted 

 to the sclerite that forms the wall of the middle division of the 

 l)ull). Ill Linypliia, the tegulum, in this restricted sense is a 

 rinj^like sclerite (Fig. 10, te^.). 



The median (ipophysis. — Arising within the distal margin 

 of the tegulum there is an appendage, only the tip of which is 

 shown in the view of the bulb figured here (Fig. 10, ;;/. a.); 

 this is the median apophysis. In many s]3iders this appendage 

 is very conspicuous; and to it have been a])i)lied several names. 

 In fact in several instances a writer has applied different names 

 to this ])arL in his descriptions of different genera. Among the 

 names that have been ap])lied to it are lamella character istica and 

 apophysis media na (Chyzer et Kulczynski '91), clavis and unca 

 (F. ( ). Pickard-Cambridge '97-'()5), and scopus (Chambcrlin 

 '04). The term median apophysis occurs frequently in descrip- 

 tions, and is the older name for this part. 



The median apophysis is articulated to the middle division 

 of the bulb near the point from which the apical division arises ; 

 and in some cases, as in Aranea, it appears to be more closely 

 articulated with a basal segment of the apical division, the radix, 

 than it is with the tegulum. 



The apical division of the bulb. — This division includes that 

 portion of the bulb which lies distad of the middle division; it 

 consists of two subdivisions: the conductor and the embolic 

 subdivision. The embolic subdivision is traversed by the ejacu- 

 latory duct and is composed of several distinct parts. In fact 

 the multiplication of parts of the embolic subdivision is the 

 most characteristic feature of the rnore specialized types of 

 palpi as contrasted with the intermediate types described above. 



The conductor. — The conductor (Fig. 10, con.) is easily 

 recognized by its relation to the embolus, which rests upon it, 

 and by its membranous texture. Its attachment to the middle 

 division of the 1)ulb is by means of an exceedingly delicate 

 membrane. 



In Li)iyphia the embolus rests uj^on the conductor through- 

 out its length; but in many genera the palpi of some of which are 

 described later, the function of the conductor is evidently to 

 protect the tip of the embolus in the unexpanded bulb. In many 

 cases the embolus is very long while the conductor is short; 

 but in every case the embolus in the unexpanded bulb occupies 

 such a position that its tip is jjrotected by the conductor. 



