484 POLYDORA CAKCA. 
of the anus, and each plate has three to five cirri, usually four. Behind the eleventh foot 
the lamelle increase greatly in size, but are inconspicuous posteriorly. Mature in May. 
SYNONYMS. 
1914. Aonides paucibranchiata, Southern. Proc. Roy. Irish Acad., vol. xxxi, No. 47, p. 100, pl. xi, 
figs. 24 a—e. 
1915: es 3 McIntosh. Ann. Nat. Hist., ser 8, vol. xv, p. 3. 
1922. of a idem. Ibid., ser. 9, vol. 1x, p. 22. 
Habitat —Dredged in Clew Bay in 24 fathoms, and Berehaven (Southern). 
The snout is acute, though less abruptly so than in A. oxycephala, and it is prolonged 
backward, to end in a peak. Four eyes occur posteriorly, the anterior pair having a larger 
space between them. The body, though much smaller, has a similar form to that of A. 
oxycephala, and it bears about ten gills anteriorly, the branchial region being thus different 
from that of the common form, in which the gills appear to be closer in the preparations, 
though that may be caused by the methods adopted in preservation. An anterior foot is 
outlined in Plate CXXXVI, fig. 8, and typical bristle in fig. 8a. In the seventy-eighth 
foot the dorsal division contains four hooks and six capillary sete. The ventral division 
has seven hooks and four capillary bristles, the two central bemg longer and stouter 
than the others. The lamelle have long, finger-shaped, amber-coloured glands. 
The tail of A. oxycephala, in the examples from Herm, is small and has dorsally two 
short conical lobes, whilst beneath are about eight smaller conical cirri, whereas in this 
species there are but two pairs of anal cirri. 
Potypora caca, Mrsted. Plate CXXVI, fig. 11—hook; Plate CXXXVI, fig. 9—dorsal 
bristle ; Plate CX XXVIII, fig. 10—hook of the fifth segment, 10a and 10b—bristles. 
Specific Characters.—Head similar to that of P. flava, with a bifid median process, which 
is continued backward to the second segment. Body fully 20 mm. long, and having from 
70 to 120 segments, terminating in a caudal funnel, with a hiatus superiorly. Fifth 
segment bears strong acicular bristles, with a distinct hook at the tip, but no spur. Branchiz 
commence on the eighth setigerous segment, and terminate, as a rule, about the fiftieth. 
About the twenty-fifth segment, in front of the caudal funnel, stout acicular bristles appear 
in the dorsal tuft and continue almost to the tip of the tail. 
SYNONYMS. 
1843. Leucodorum cecum, Cirsted. Annul. Danic. Consp., p. 39. 
1844. » idem. Arch. f. Naturges., p. 106, pl. ui, figs. 13—16. 
es 5 m  ieleyin, Ine IWlew., jos TE 
1865. Leucodore cxca, De Quatrefages. Annel., t. 11, p. 302. 
1867. 3 cecus, Malmgren. Annul. Polych., p. 95. 
1870, Polydora fluva, Claparéde. Suppl. Annél. Naples, p. 123. 
1873. Leucodora cxca, Willemoes-Suhm. Zeitschr. f. wiss. Zool., Bd. xxiii, p. 348, pl. xviii, figs. 4—5. 
1874, Leipoceras uviferum, Mobius. 2 deutche Nordpolarfahrt, ii, p. 254, pl. i, figs. 10—20. 
1879. Polydora ceca, Webster. Annel. Virgin. Coast, p. 52, pl. ix, figs. 119—122. 
1880. a ciliata, var. minuta, Langerhans. Zeitschr. f. wiss. Zool., Bd. xxxiv, p. 91. 
