36 THE VOYAGE OF H.M.S. CHALLENGER. 



nematopliore of Ayhiophenia macgiUtcraui, though Lirge, is very far from attainiug 

 the width of the hydrotheea to which it is attached, and does not, either in size or form, 

 depart so much from the normal condition as to justify us in assuming it as the ground 

 on which to base a distinct section of the phylactocarpal Phimidaridce {Aglaojyhenia of 

 Kirchenpauer in its widest sense) ; and the remaining small number of species which 

 Kirchenpauer places in his Pachijrhijnchia do not seem to afford any stronger grounds than 

 AgJaoplienia macgiUivmyi for the creation of a separate systematic group. In the long 

 corbula, with its closely adnate costse and parietal ridges, and in the even margin of the 

 hycbotheca, more important differences may perhaps be recognised, but still nothing to 

 demand a separation from the other members of the genus. 



A closely allied if not identical form — the AgJaophenia cupressina of Lamouroux, has 

 been identified by Kirchenpauer with a Plumularian brought by Semper from the Pelew 

 Islands, where, according to Semper, it is known Ijy a vernacular name suggested by its 

 stinoing properties. Another of the Challenger species {Ljjtocarpvs secunchis, see below, 

 p. 42), likewise brought by Semper from the Pelew Islands, would seem, according to 

 the report of it given l)y this zoologist to Kirchenpauer, to 1>e also one of those Hydroids 

 whose formidable stinging powers cause it to be dreaded by the natives. 



Aglaopfienia macgillin'aiji attains a size greater than that of any other Aglaoplienia 

 with which I am acquainted. Though the specimen from which the drawing has lieen 

 made had lost a portion of its proximal end, what remains of the colony measures in 

 height fifteen inches. 



Dredged at Zamboanga, Philippines, 30th January 1875, from a depth of 10 fathoms. 



Aglaofhenia jiUcula , n. sp. (PL XI. figs. 1-6). 



Tvopliosome. — Colony attaining a height of about three inches ; stem monosiphonic, 

 simple, rooted by a creeping tubular fibre ; hj'drocladia al)0ut one-fourth of an inch in 

 length, alternate. Hycfrothecse deep, thimble-shaped, margin serrated, with the median 

 tooth slightly longer than the lateral teeth ; intrathecal ridge near the base of the 

 hydrotheea, extending oblicjuely forwards and upwards ; mesial nematophore adnate to 

 the walls of the hydrotheea for about three-fourths of their height, and then becoming 

 free as a beak-like process which scarcely overtops the margin ; lateral nematophores 

 tubular, overtopping the margin of the hydrotheea. 



Gonosome. — Corbulje somewhat crescentic, with about seven pairs of costa3, which are 

 adnate to one another by their edges, with a row of tubular denticles at the lines of junc- 

 tion, and with a spur-like denticle at the proximal end of each row ; a single free co.sta 

 with dentated edges at the proximal end of the corbula. 



Other corbulfe having the costa3 all free occur in the same colonj*. 



The simple stems of Aglaoplienia JiUcida spring from the creeping hydrorhiza, in 



