Pogonophora from Tehuantepec — Adegoke 
191 
Fig. 5. Galathealinum mexicanum Adegoke sp. 
nov. Part of paratype enlarged to show coarse fibers 
and details of constricted segmental junctions, X 5. 
Fig. 7. Galathealinum mexicanum Adegoke sp. 
nov. Part of paratype enlarged to show details of 
segmental junction and remnants of segmental frills 
at nodes. 
Fig. 6. Galathealinum mexicanum Adegoke sp. 
nov. Part of paratype enlarged to show three encrust- 
ing annelid tubes, X 5. 
those of G. hrachiosum Ivanov, whose diameter 
ranges from 2.0 to 2.6 mm, from which it ma y 
be readily distinguished by the longer segments 
(about 4.0 mm long as against 1 mm in G. 
hrachiosum', see Ivanov, 1963: Fig. El62). 
Moreover, the coarse fibers in the new species 
measure 15-22p, whereas they are 7-1 2p thick 
in G. hrachiosum. 
From G. hruuni Kirkegaard, the new species 
may be distinguished by its larger dimensions, 
relatively weaker segmental frills, and thicker, 
coarser fibers (2-4^ thick in G. hrunni ). 
The new species may be readily distinguished 
from G. arcticum Southward by its larger diam- 
eter (1.33-1.95 mm in the latter) ; larger 
length-diameter ratio of each segment, which is 
about 2 in the new species and 1 in G. arcticum ; 
and the thicker coarse fibers, which are only 
l-2p thick in G. arcticum. 
The longest fragment represented in the col- 
lection is 147.5 mm long. As the extreme ante- 
rior and posterior ends of this tube are not 
represented, and because of the rather minor 
variation in taper between the two ends (ante- 
rior diameter 2.5 mm, posterior diameter 2.2 
