Pogonophora from Tehuantepec — Adegoke 
basis of soft part anatomy, remains of well- 
preserved tubes are also known to be sufficiently 
reliable for "specific diagnosis” (see Hartman, 
1961:546; Ivanov, 1963:120). The latter 
author firmly established the validity of this 
contention by constructing a dichotomous key 
for the identification of most Recent pogonc- 
phoran species from remains of their tubes 
(Ivanov, 1963:456-461). The characters of 
the tubes described and figured in this report 
readily distinguish them from the three pre- 
viously described species of Galathealinum. It 
is hoped that, in the future, preserved material 
from the same area will provide data on the 
nature of the soft part anatomy of the new 
species. 
SYSTEMATIC DESCRIPTION 
Phylum pogonophora Johansson, 1937 
Order thecanephria Ivanov, 1955 
Family polybrachiidae Ivanov, 1952 
Genus Galathealinum Kirkegaard, 1956 
Galathealinum Kirkegaard, 1956, Galathea 
Rept. 2:79-83. 
type species: Galathealinum hruuni Kirke- 
gaard. 
Galathealinum mexicanum sp. nov. 
Figs. 1-7 
diagnosis: Galathealinum with elongate, 
cylindrical, segmented tube; circular cross-sec- 
tional outline; average tube diameter 2.0-2. 5 
mm; covered along entire length by thin, felt- 
like layer of fine and coarse fibers ; individual 
coarse fibers at segmental junction about 15— 
22p thick; segment length approximately twice 
the diameter. 
description: This species is represented by 
fragments of dried tubes only. The tubes are 
brownish-gray to dark-gray, elongate and slen- 
der. The longest fragment (holotype, Fig. 1) 
is 147.5 mm long. Maximum diameter 2.5 mm, 
minimum diameter 1.96 mm. Externally, the 
tube is divided into numerous prominent seg- 
ments (see Figs. 1-6). These segments have a 
i circular cross-sectional outline and are of rather 
i uniform length, each measuring 3. 8-4.9 mm. 
The widened funnel-like frills that are prom- 
inently shown at the nodes of the described 
189 
Fig. 1 . Galathealinum mexicanum Adegoke sp. 
nov. Tubes from Univ. Calif. Mus. Paleo. locality 
B-7469, Gulf of Tehuantepec, Mexico. Holotype, 
ucmp 32882. Entire specimen showing long, curved, 
segmented tube, X 3/ 4 . 
species of Galathealinum are only poorly pre- 
served on the dried tubes of the present species 
(Figs. 3, 7). The coarse fibers generally asso- 
ciated with these frills are well developed, how- 
ever, and are more abundant at the nodes than 
in the much longer internodes. The exterior of 
the tube is coated by a thin, friable, feltlike 
layer, mostly composed of numerous, very fine, 
light-brown fibers, and few, coarse, reddish- 
brown, glistening fibers. The latter also pene- 
trate the tube wall and appear as faint ridges on 
the otherwise smooth interior surface. About 
60—80 coarse fibers are present in each inter- 
node. Though essentially transverse, they are 
