'.llDl 



The Palpi of Male Spiders 



183 



A lamelliform embolus. — In this type the embolus is flattened, 

 and may bear a greater or less number of apophyses ; an example 

 of this type is found in Lepthyphantes miniita (Fig. 25, 2.) 



A spiral embolus. — In the spiral type, as seen in Agelena, for 

 example, the embolus is long, slender and coiled; and, in a well- 

 expanded specimen, it is seen to be composed of three distinct 

 parts: first, the wall of the convex side is densely chitinized, 

 forming a gutterlike sclerite, which may be termed the trunk 

 of the embolus (truncus) (Fig. 25, S, t. e.) ; second, the greater 

 ]jart of the wall of the embolus is membranous, and forms a 

 loose flap along the 

 concave side of the 

 organ, which contains 

 the ejaculatory duct; 

 this flap (Fig. 25, .?, 

 p. p.) may be desig- 

 nated the pars pendula 

 of the embolus; third, 

 at the distal end of the 

 pars pendula, there is 

 a triangular, chitinized 

 area, through which 

 the ejaculatory duct 



opens (Figs. 25, 3, a. s.), thi^ may he termed the apical sclerite 

 of the embolus. 



The pars pendula and the apical sclerite may be completely 

 withdrawn into the trunk of the embolus, so that only the latter 

 is visible; the embolus then appears to be merely a strongly 

 chitinized style ; it is in this condition that it is usually seen and 

 described. 



CONCLUSION. 



In the preparation of this paper many palpi other than 

 those figured here have been studied; and it is believed that the 

 series examined has been sufficiently large to warrant the con- 

 clusions given regarding the fundamental parts of the genital 

 bulb. There remains to be determined the manner in which the 

 different types of palpi have been specialized in other families of 

 the order, and the details of the modifications characteristic of 

 genera. This, however, is too great an undertaking to be at- 

 tempted at this time, and must be left for those who monograph 

 the different families. 



Fig. 2.5. Three types of embolus. 



