1968] 
Chickering — Genus Ischnothyreus 
85 
from PME by about half their radius. PME contiguous and sep- 
arated from PLE only by a line. Height of clypeus equal to about 
5/8 of the diameter of ALE. Chelicerae: well developed; nearly 
vertical and parallel; fang normal, without such a basal knob as 
occurs in I. peltifer (Simon) and /. omus Suman; apparently without 
definite teeth along fang groove. Lip simple, without special modifica- 
tions. Maxillae: convergent; modified distally (Fig. 13). Sternum: 
essentially as in I. peltifer (Simon) ; fourth coxae separated by 1.25 
times their width. Legs and spines essentially as described for I. 
peltifer (Simon) by Dr. Petrunkevitch (1929) and Miss Bryant 
(1942). Palp: closely resembles this organ in /. peltifer (Simon) 
but with certain obscurely distinctive features (Figs. 14-16). Ab- 
domen: with dorsal scutum as in Figure 18; epigastric and ventral 
scuta not clear but, apparently, like those in /. peltifer (Simon) ; 
genital aperture as in Figure 17. Color in alcohol: essentially as 
described for I. peltifer (Simon) but somewhat lighter; oval areas 
on carapace somewhat darker than surrounding regions; palp typical- 
ly dark brown. 
Female paratype. Total length 2. mm including somewhat ex- 
tended spinnerets and chelicerae. Carapace .75 mm long; .64 mm 
wide; .31 mm tall. Eyes: essentially as in male with minor variations. 
Chelicerae, maxillae, lip and sternum all essentially typical of females 
of the genus; no teeth observed along the fang groove. Legs and 
spines apparently also typical of females of the genus. Abdomen : 
with a well developed dorsal scutum (Fig. 19) ; epigastric and ventral 
scuta appear to be somewhat distinctive (Fig. 20) but the epigynal 
area is poorly delineated. 
Records. The described female paratype together with three ad- 
ditional female paratypes were taken on Nevis, B. W. I., Sept. 24- 
29, 1966. One male was collected on St. Vincent, B. W. I., Oct. 
15-24, 1966; one male was taken on St. Thomas, U. S. V. I., Feb- 
ruary 14, 1964. 
Bibliography 
Bonnet, Pierre 
1957. Bibliographia Araneorum. Toulouse. Vol. 2(3). 
Bryant, Elizabeth 
1940. Cuban Spiders in the Museum, of Comparative Zoology. Bull. 
Mus. Comp. Zool. 86(7): 249-532, 22 pis. 
1942. Notes on the Spiders of the Virgin Islands. Bull. Mus. Comp. 
Zool., 89(7): 317-363, 3 pis. 
1948. The Spiders of Hispaniola. Bull. Mus. Comp. Zool., 100(4): 331- 
447, 12 pis. 
