106 THE PLUMULARID.E. 



claclia divided into regular short internodes, eacli of which is divided back of the iutrathecal ridge 

 of the hydrotheca by an internal ridge. Hydrothec;e stout, closely approximated, expanded 

 above, with the anterior profile doubly curved, margin with nine strong subequal teeth, iutra- 

 thecal ridge strongly developed and projecting straight forward and upward; supracalycine 

 nematophores stout, rather geuiculate, slightly overtopping the hydrotheca; mesial nematophore 

 strong, reaching to about the middle of the hydrotheca, anterior profile regularly convex, the 

 nematophore being adnate to the hydrotheca almost to the end of the former, where there is a broad 

 terminal aperture; cauliue nematophores, three to each inteniode of the stem, one being just 

 below the proximal hydrotheca of each hydrocladiuui and two being on the front of the inteniode. 



Gonosome. Corbula' rather long and slender, with 12 to 14 pairs of corbula leaves, each of 

 which bears a row of nematophores along its distal edge and a slightly larger one at its base. 



Distribution. Found thrown up on the beach at Sullivan's Island, Charleston Harbor. 

 (McCrady.) 



1 was unable to secure either specimens or figures of this species before the plates for this 

 work were printed. Among some material recently sent me for identification by Prof. H. L. 

 Osboru, of Ilaiuliue University, I found specimens that appear without a reasonable doubt to 

 belong to this species. The locality from which the specimens were taken was not given, but 

 Professor Osborn thinks they were from Beaufort, North Carolina. 



This species is very closely allied to Aglnnphi'iiin plinmi of the British coast, but a direct com- 

 parison with specimens from Plymouth, England, shews that the American species has hydrotheca' 

 with a less concave profile above the mesial nematophore and a much longer and more slender 

 corbula. 



AGLAOPHENIA TRICUSPIS McCrady. 



Aglaoplieniu triciispix McC'RADY, (iymii. Charleston Harbor, 1857, p. 101. 



.li/l(ii>i/lieiiin irii-unpiii Louis AGASSI/,, Gout. Nat. Hist. IT. S.. 1862, IV, p. 3~>S. 



Ai/hiniilieniii trii'impis ALEXANDER AGASSIZ, X. A. Acaleph.. 18U5, p. 140. 



At/laoplieiitti IriruxpiK KIRCHENPAUER, Ueber die Hydroidenfam. I'lumularid.-i-, 1872, Pt. 1. p. 27. 



This species grows in solitary plumes, much taller than those of A. prlasgica and shorter than 

 those of A. crifttntit. The plumes also are of broader expanse than in the latter species and the 

 individual polyp cells are quite different. The three cusps, which are placed as in the species 

 mentioned, are proportionately long and slender, or, which is the same tiling, the polyp cell 

 between them is quite shallow, and its rim, instead of appearing distinct from the single cusp 

 behind it, appears to be united with it as with the others. I have also been unable to distinguish 

 any denticulations on the rim, and these are quite conspicuous in the other two species. 



The prolific vesicles of this species are as yet unknown. This species was found growing just 

 below dead low-water mark, on the submerged rocks of one of the upper jetties of Sullivan's Island. 

 It was taken in midsummer. 1 



THECOCARPUS, new genus. 



Trophosome. Stem fascicled, usually with the component tubes diverted from their course at 

 intervals to form somewhat flattened protuberances. Hydrotheca? with one or two large anterior 

 teeth, the remainder being small or reduced to minute siuuations; mesial nematophores one or two, 

 less than half the height of the hydrotheca; intrathecal ridge inconspicuous. 



G-onosome. Corbula composed of widely separated leaves, each bearing a hydrotheca near its 

 base and a row of nematophores on its distal portion. There are usually three or more hydrothecse 

 between the corbula and the stem. 



In looking over the very large series of American Aglaophenise several were found that differed 

 from all the others and agreed among themselves in the possession of the characters given above. 

 Aglaophenia myriophi/Uum may be taken as a type of this genus, and in it would also be included 

 Aykiopltenia radicellatu Sars. 



Allman, in the Challenger Report 2 placed these species in the genus Lytocarpus, and did not 



'Original description. I have been unable to find either specimens or later descriptions of this species. 

 * Challenger Report, Hydroida, Pt. 1, pp. 12, 40. 



