Lithoglytes hirsutus — Tomlinson 
301 
The mouth parts (Figs. 2-4) are typical for 
the genus, being composed of a pair of man- 
dibles with palps and two pairs of maxillae. 
Each mandible has four strong teeth, the inner 
one bearing short bristles. The mandibular palp 
exceeds the mandible in length; with long, soft 
bristles on the edges near the tapering point. 
Each first maxilla is armed with two strong 
teeth, numerous bristles, short teeth along the 
cutting edge, and has the usual apodeme. The 
second pair of maxillae are large and soft, and 
have numerous flexible bristles distributed along 
their edges. These close-set appendages serve 
as posterior limits to the mouth field. 
The mouth cirri ( Fig. 7 ) have a two-jointed 
pedicle upon which the two bristle-bearing 
rami articulate. They arise below the mouth 
parts but terminate above them, frequently 
curving outward at the tips. The anterior ramus 
has five segments and the posterior ramus has 
three segments. The segments of the rami are 
equipped with numerous bristles, which make 
the determination of the number of segments 
very difficult. 
There are four pairs of biramous, multiseg- 
mented terminal cirri, on two-segmented pedi- 
cles. The slanted articulation between these 
pedicular segments is characteristic of the genus. 
The rami are armed with single long setae on 
the outer edges of every second to sixth artic- 
ulation. The setae on the inner edge of the 
terminal cirri alternate between pairs of long 
setae at the articulation and pairs of shorter 
setae toward the middle of the segment 
(Fig. 5). 
A pair of two-jointed uniramous caudal ap- 
pendages occurs at the posterior end of the 
body. The total length of the caudal appendage 
is about Vi the length of the pedicle of the 
posterior terminal cirrus. 
The burrow of the female appears in the sur- 
face view as a pointed oval (Fig. 6). It is 
deeper than it is long. The walls are nearly 
perpendicular to the surface, and rounded at 
the bottom. The depth of the burrow appears 
to be slightly more than the greatest diameter 
of the animal in dried specimens. It is assumed 
that the living animal closes the burrow open- 
ing with the hardened, hairy apertural area 
of the mantle. 
MALE: Dwarf males resembling cyprid lar- 
vae were seen, but being dried they were much 
distorted, and whether or not they were truly 
mature stages could not be determined. Of the 
11 males studied, none had the very reduced 
baglike shape of many acrothoracican males, 
nor the attenuated stalk of the male of Lit ho - 
glyptes spinatus. They were of a size and shape 
one would expect of a cyprid larva which had 
lost its bivalved carapace. The presence of a 
penis could not be ascertained. 
L. hirsutus is the first member of the genus 
to be found in the central Pacific. Of the other 
species in the genus L. indicus Aurivillius, L. 
ampulla Aur., and L. hicornis Aur. are from 
the Java Sea and Indian Ocean, and L. spinatus 
Tomlinson and Newman is from Jamaica. 
L. hirsutus can be distinguished from L. bi- 
cornis, L. ampulla , and L. spinatus by the ab- 
sence of the apertural hooks and/ or spines 
borne by the latter three species. This new 
species may be distinguished from L. indicus, 
which also lacks the hooks and spines, by the 
presence of the "hairs” on the mantle aperture 
and by its small size (2 X 1 mm rather than 
6X^ mm). 
REFERENCES 
Aurivillius, C. W. S. 1892. Neue Cirripeden 
aus dem Atlantischen, Indischen und Stillen 
Ocean. Ofversigt af Kongl. Vet.-Akad. Forh. 
Stockholm 49 (3): 133-134. 
Tomlinson, Jack T., and William A. New- 
man. I960. Litho glyptes spinatus, a burrow- 
ing barnacle from Jamaica. USNM Proc. 
112 (3443): 517-526. 
