THE PLUMULARID.E. 8i 



Lytocarpia, and Macrorhynchia. His first section, Culathopliora, included the genus Aglaoplienin 

 as used here. In his third section, Lytocnrpiu, he includes forms snch as Aglaophciiin myriophyllum, 

 which Altaian ' places in the genus Li/tocm-pnx, Hale - regards as a part of the genus AgluoplieniH, 

 and the present writer would place in a new genus, Thecocnrpus. 



It will be seen that I here agree with Bale in the opinion that the corbula of Tliceociirpus is a 

 true corbula, differing from that of Aglaophenia mainly in bearing hydrothec;e at the liases of its 

 leallets. 



Distribution of tin: American species of Aglaophenia. 



KKY To THE AMERICAN SPECIES OF AGI.AI IPIIENIA. 



Axis of hj'drothwa foriniti"- an acute angle with hyilrochicliiini. Ifyilro- 

 rhulial interiioiles with more than two distinct aeptal ridges. 



rhi/ncTiocarpa. 



Sujiracalycine nematophorea slightly overtopping the hydrothoca. 



calamus. 



Mesial neraatopbore short, without con- 

 striction or 8e])tal ridiri 1 . tomiing an 

 acute angle with h\ ilnithcca. Marginal 

 teeth even and regular. l!i</i<l/i group. 



Marginal teeth on ale vel with base of next hydrothecanbove. . .rii/iiln. 



Marginal teeth distinctly below the base of the next hydrotheca 



above dnliin. 



Axis of hydrotheca nearly or ([itite parallel with that of hydrocladinni. 



llydrocladia springing from distal ends of stein, joints. . .lojiliocurjui. 



Hydrocladia s|iringing from near middle of stem .joints. . . .apoi'arixi. 



Colony branched, over 4 inches high. Hydrotheca' approximated. 



floirersi. 



Colony unbrauched. Hydrotheca' rather close set. Corbula arcu- 

 ate eli ga ii s. 



' Challenger Report, I'lnmnlarida', pp. 12, 40. 



2 See The- ( Sonera of the Plumulariida-, p. 12, etc., for au excellent discussion of this and other points of interest to 

 the systenjatist. 



