THE POLYCHiETOTIS ANNELIDS OF PORTO RICO. 
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farther back the parapodiura becomes more pointed, and the division into anterior and posterior lips 
is not evident. (See fig. 35 of forty-fifth parapodium.) A stout dorsal aciculum and three smaller 
ventral ones bent and toothed at end. Aciculae extend into the dorsal cirrus in all parapodia. Ventral 
cirrus stout and short on anterior segments (fig. 34); very small on posterior ones (fig. 35) . 
Setse of posterior segments of three kinds. Some like those of anterior segments. In addition, 
comb-shaped setse and compound setse, with short toothed terminal joint. (See figs. 36a and 365.) 
On the ventral surface of the dorsal cirrus is a peculiar rounded lobe, which I suppose must be a sense 
Figs. 33-366 . — Eunice auriculaia. Fig. 33, Head, x 12. Fig. 34, Anterior parapodium, x 19; 
s. org., sense organ. Fig. 35, Forty-fifth parapodium, x 19. Figs. 36a, 366, Set®, x 143. 
organ, though I have not yet had opportunity for a careful study of it. It is present, though very 
small, on the first segment, and becomes very prominent farther back. (See figs. 34 and 35, s. org . ) 
It contains no pigment, so can hardly be optical in function. A more complete account is reserved for 
a later paper. 1 No eyes could be discovered on the alcoholic material. Jaws: 1, long, pointed; 2, 
right 4 to 5, left 6; 3, right 5, left 5. Dark brown spot on outer ventral 
side of 4. 
Color light brown. The posterior segments had been lost in all the 
specimens. The animals live in tubes of mud with thick (2 mm.) walls. 
Collected from stations 6066 and 6067. 
Eunice culebra, n. sp. 
The collection includes one small specimen which 1 at first took for 
a species of Nicidion. Only about 50 of the most anterior segments were 
preserved; the most posterior show a short outgrowth on each dorsal 
cirrus, representing a gill; it is evidently an immature Eunice. Head 
deeply bilobed, with a pair of eyes near bases of the inner paired tenta- 
cles. Tentacles slender, unpaired, three times as long as head. Median 
paired three-fourths as long as head. Outer paired a little shorter than 
median. Tentacular cirri slender, a little over half as long as buccal cirrus. 
Parapodium (see fig. 37) with a single stout aciculum. Dorsal cirrus long, ventral cirrus short, blunt, 
with a swollen base. Ventral setse compound, terminal joint with a stout tooth behind apex. Dorsal 
sette long, curved, pointed, slightly enlarged near the end. 
I have been unable to identify this species, and have given it, provisionally, the above name. 
Collected from Ensenada Honda, Culebra. 
Fig. 37.— Parapodium of Eunice 
culebra , X 46. 
Eunice rubra Grube. 
Eunice rubra Grube, Annuiata Oerstediana, 1856-57, p. 59. Quoted from Ehlers, Annel. of Blake, p. 87, pi. 26, figs. 1-11. 
Specimens very immature, but agreeing so closely with this species in structure of tentacles 
setae, and acicuke that I have placed them here. From Arroyo, Puerto Real, and station 6085. 
1 Later study shows that this organ is essentially identical in structure with the lateral line organs described by Eisig 
in the Capitellidce. (Fauna u. Flora Golf v. Neapel, xvi, p. 76.) 
