REPORT OF THE DIRECTOR 1923 83 
A FOSSIL SPECIES OF CADDO (OPILIONES) FROM THE 
BALTIC AMBER, AND ITS LIVING RELATIVES 
BY SHERMAN C. BISHOP AND C. R. CROSBY 
Caddo is a rather aberrant genus characterized by the greatly en- 
larged eyes and is represented by only two very rare living species 
restricted so far as known to the eastern United States and Canada. 
It was therefore of great interest to find that an undoubted repre- 
sentative of the genus was described by Koch and Berendt (Die 1m 
Bernstein organischen Reste. v. 1, pt 2, p. 101, pl. 15, fig. 125. 1854) 
from the early Tertiary Baltic amber under the name of Platy- 
bunus dentipalpus. This should be transferred to the 
modern genus Caddo. 
Through the kindness of Dr Walther Horn and the authorities of 
the Berlin Museum, we have had the opportunity to study the type 
specimenof Caddo dentipalpus and have had a new figure 
prepared. It is very closely related to C. agilis. The eyes are 
relatively as large as in that species and the eye-tubercle is of the 
same form. The eye is surrounded by a dark ring. The segments 
of the body can be distinctly seen and are much the same as in C. 
agilis. Only the first and the basal part of the second segment 
of the chelicerae are visible and appear unarmed. The palpus is 
nearly unarmed on the dorsal and outer surface but on the inside 
there is a bunch of stiff hairs at the tip of the femur (on a distinct 
swelling) and the inner surface of the succeeding segments is 
densely clothed with similar hairs. The underside of the femur 
bears three spines arranged almost the same as in C. agilis. 
The legs seem to be longer than in that species. 
The treatment of the genus Caddo in Roewer’s excellent revision 
of the Opiliones Palpatores, part 2 (Abhandl. a. Gebiete, Naturw. 
Hamburg, v. 20, Heft. I p. 33, 1912) is unsatisfactory due to no 
fault of the author. 
Banks described the type species, C. agilis, (Proc. Ent. Soc. 
Wash., 2:249, 1892) from immature specimens but did not mention 
thepracty | Grosbya (Journ Neo Ent Soc. 12.253, 1904) described 
two species which he referred to this genus, glaucopis and 
boopis. In the same number of this journal, page 256, Banks 
published a note stating that the original description of agilis was 
based on immature specimens. A comparison of specimens later 
showed that agilis and glaucopis are the same. Crosby 
(Ent. News, 18:161, 1907) published a note to this effect. Roewer 
overlooked this publication and retained glaucopis as a distinct 
species. 
