1963] 
Abalos and Baez — Spermatic Transmission 
205 
with his chelicera. In pseudoscorpions, the male deposits a spermato- 
phore on the ground, then pulls the female over it (Vachon, 1938). 
In scorpions, various authors have recently described almost simul- 
taneously the complete mating act, in which a spermatophore is 
fixed by the male on the substratum (Angerman, 1 955 J Alexander, 
1956, fide Alexander and Ewer, 1957). It has been reported for 
South American scorpions by Bucherl (1956), Matthiesen (i960) 
in species of Tityus, and Zolessi (1956) in Bothriurus; the male 
paraxil apparatus (sclerotized support of the spermatophore) was 
described for a representative of the family Bothriuridae by Abalos 
( 1:955 ) > as an element of the internal anatomy of the male and 
without taking into account its possible function. 
That all arachnids with indirect fertilization employ spermato- 
phores permits us to expect a similar mechanism in spiders. Alexander 
and Ewer (1957) suggest that a spermatophore could have inter- 
vened in the sperm transmission of their hypothetical protoarachnid. 
We do not believe that in the theridiids mentioned (16, 29) the 
apical element of the male palpus acts as a simple plug to prevent 
the loss of seminal liquid from the female reproductive organs. Nor 
can the flagellar element of Latrodectus act as a plug; it is much 
too slender to occlude the seminal receptacle or the ducts. However, 
the apical element of Metepeira species closely fits the entrance of 
the seminal receptacle, which, lacking a connecting canal, is almost 
open to the exterior. Here the element might assume the role of a 
plug. 
In Argiope argentata and Argiope sp. the apical element (the 
posterior portion of which can be seen in fertilized females when the 
abdomen is inspected from below) is fixed by a granular mass that 
at the same time obstructs the access to the seminal receptacle (fig. 
13). This mass recalls the spermatocleutrum of the scorpions; its 
presence indicates that fertilization has taken place. 
Explanation of Plate 23 
Figs. 20-22. Latrodectus geometricus. Fig. 20. Seminal receptacle with apical 
element. Fig. 21. Seminal receptacles of virgin female. Fig. 22. Male palpus 
tip, with embolus. 
Figs. 23-25. Metepera sp. Fig. 23. Seminal receptacle with apical element. 
Fig. 24. Apical element of embolus extracted from seminal receptacle. 25. Male 
palpus with apical element of embolus. 
Figs. 26-28. Argiope argentata. Fig. 26. Apical element of embolus extracted 
from seminal receptacle. Fig. 27. Embolus in the male palpus. Fig. 28. 
Argiope sp., seminal receptacles and atrium with several apical elements. 
Figs. 29-30. A chaearanea tepidariorum. Fig. 29. Seminal receptacle with 
apical elements in its interior. Fig. 30. Embolus of palpus. 
