1965 ] Reiskind — Genus Sicarius 219 
Sicariidae: No web, unique ethological specializations outlined 
below. 
The family Sicariidae (s.s.) contains the single genus, Sicarius. 
The genus has a predominantly south temperate distribution with 
species also described from Peru, Chile, Argentina and Southern 
Africa, with single species found in eastern Brazil, the Galapagos 
Islands and Costa Rica. Merian (1913) states that this “distribu- 
tion meridionale isolee est le resultat de la retraite de [ce genre], de 
la zone tropical vers le Sud.” On biogeographic grounds Merian 
considers Sicarius part of an ancient fauna. 
The simple genitalia in the Sicariidae place them in the ecribellate 
spider group known as the haplogynes. In regard to systematics, 
“spiders lacking distinctive genitalia, in particular the Haplogynae, 
tend to have been neglected rather than to have stimulated interest 
in extra-genital characters” (Cooke, 1965). These extra-genital char- 
acters must include aspects of the external morphology (as used in 
Cooke’s study of Dysdera) as well as several non-morphological char- 
acters — e.g., ecological and ethological ones. 
In order for a character to be taxonomically useful, whether mor- 
phological or not, it must be comparatively constant in the taxon 
being studied. 
Sicarius exhibits three behavioral traits that are of potential sys- 
tematic value: 
1. Stridulation - When disturbed the spider will rub the femur of 
its pedipalp against ridges on the chelicerae, producing bee-like buzzing 
(Simon, 1893 of the South African species). Simon suggests that the 
buzzing frightens enemies. 
2. Cocoon Construction - The structures built by an organism are 
the physical summation of certain behavioral patterns. In spiders 
these structures include webs and egg cocoons. As a hunting spider, 
Sicarius does not spin webs but constructs egg cocoons that are char- 
acteristically covered with an earthy coating. Simon (1899) utilized 
this ethological character in noting the difference in the cocoons of 
Sicarius hahni Karsch (S. W. Africa) and ? S. peruensis Keyser- 
ling (Peru). 
3. Self-burying - This phenomenon, found in two species of South 
American Sicarius , is reported in this paper. 
Two species of Sicarius collected by Dr. H. W. Levi in South 
America were used in this study. Because of an inadequate knowl- 
edge of the taxonomy of this genus I have designated by numbers 
the two distinct species discussed in this paper, and have so labelled 
the specimens and deposited them in the Museum of Comparative 
