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PACIFIC SCIENCE, Voi XVIII, April 1964 
forms having modified spines in the fifth seg- 
ment (9). 
Tripoly dor a spinosa was found at Eniwetok 
Atoll on the lagoon side of Rigili in coarse 
sandlike rock, and on the lagoon side of Bo- 
gombogo in beach rock from a high intertidal 
region. It was associated with Lysidice collaris 
Grube in both areas. 
DISCUSSION 
Geographic and Ecologic 
Hartman (1954:619) said of the Marshall 
Islands polychaetes, "The annelid fauna of this 
area clearly has an affinity with fauna from 
other parts of the Indo-Pacific” Of the known 
forms in the present collection, Pseudopoly dor a 
antennata and Polydora armata , the following 
can be said. Pseudopoly dor a antennata has been 
reported from many parts of the world, in- 
cluding South Africa, the Mediterranean region, 
the English Channel, and, for the Indo-Pacific, 
from Krusadai Island, Gulf of Manaar, Indian 
Ocean, and Japan. Polydora armata has been 
found in all these areas with the exception of 
Krusadai Island and with the addition of Ceylon. 
The two species are thus widely and similarly 
distributed geographically, indicating that they 
are both cosmopolitan forms in a general pat- 
tern; however, they are restricted in ecological 
distribution. Pseudopoly dor a antennata has been 
found in sand and mud, in some cases from 
polluted regions. Polydora armata has been 
found as a boring form closely associated with 
calcareous materials. These two are representa- 
tive of the Indo-Pacific fauna but in no way are 
restricted to that general region. Determination 
of the endemicity of the new species must await 
further data. 
Reish ( 1959), in a study of marine pollution 
in the Los Angeles-Long Beach Harbor area, 
included Pseudopolydora paucibranchiata (Oku- 
da) as one of the indicator organisms. Pseudo- 
polydora antennata , as a close relative of the 
above species and because of its niche, should 
receive consideration as a possible indicator 
organism in any future pollution surveys in areas 
in which it is endemic. 
The bulk of the forms in the present collec- 
tions were closely associated with calcareous 
materials. Hartman (1954) stated, "Most of the 
annelids may be regarded as having a destructive 
effect on the reef building processes of corals or 
coralline algae. . . . Polydora . . . may perform 
the same function rasping with the aid of modi- 
fied setae.” In addition to these modified setae 
of the fifth many polydorids described from 
calcareous materials have heavy posterior noto- 
podial spines which should be considered as in- 
strumental in any process of mechanical boring. 
Known forms having these notopodial spines 
include Polydora hamata, P. caulleryi , P. armata, 
P. caeca , and P, hoplura . Additional species 
described in this paper include Pseudopolydora 
corallicola and Tripolydora spinosa. 
Hartman (1954) presented a short review 
of the effect of annelids' on coral atolls, in which 
polychaetes were suggested by one worker to be 
the most important boring animals in coral 
rock. In this regard it would be extremely valua- 
ble to supplement the past qualitative studies 
on coral-boring forms with future quantitative 
studies to better characterize the roles of respec- 
tive agents in coral destruction and the over-all 
significance of each. 
Systematic 
The generic breakdown of the polydorid 
forms has been unstable since the late 1800 s 
and at the present time no one arrangement is 
accepted by all workers. 
Bose (1802) established the genus Polydora; 
in later works Carazzi (1895) introduced the 
subgenus Boccardia , and Mesnil (1896) the 
separate but closely related genus Garazzia . Many 
subsequent workers accepted an arrangement of 
subgenera Polydora ( Polydora ) and Polydora 
( Carazzia ) but retained Boccardia as a separate 
genus. Fauvel ( 1927 ) treats all three groups as 
subgenera, as do Okuda (1937) and Berkeley 
and Berkeley ( 1952 ) . 
Hartman (1959), in her catalog of the poly- 
Fig. 4. 1—5, Polydora tridenticulata, n. sp. 1, Anterior end, X200; 2—4, setae of fifth (different views), 
X2000; 5, pygidium, X200. 6-9, Tripolydora spinosa, n. gen., n. sp. 6, Anterior end, XI 50; 7 , setae of fifth, 
X750; 8 , trifid hooded hooks, XI 800; 9, posterior notopodial spines and pygidium, XI 50. 
