96 AMERICAN HYDROIDS. 



AGLAOPHENIA CONTORTA, new species. 

 (Plate XX, figs. 5-7.) 



Trophosome. Colony sparsely branching, attaining a height of about 4 inches in the incomplete 

 specimens examined; stem not fascicled, of very delicate texture, divided into regular iuteruodes, 

 each of which bears a hydrocladimn, at least on the distal portion of the stein; hydrocladia 

 alternate, closely approximated, divided into regular internodes by oblique nodes; each in tern ode 

 has a strong internal ridge reaching clear around its cavity nearly opposite the intrathecal ridge, 

 and another running obliquely from just under the supraealycine nematophores, and reaching 

 nearly around the interuode. Ilydrotheca- small, very closely approximated, exceedingly thin and 

 hyaline in structure, rather deep, with an enlarged proximal portion jind an expanded and everted 

 distal portion ; margin with its anterior lip greatly produced forward so as to overhang the 

 remainder of the hydrotheca; anterior tooth strong and sharp, two lateral broad and shallow 

 teeth with a long sinuosity between them; intrathecal ridge low, plainly marked and oblique; 

 supracalycine nematophores rather small, curved upward and forward, and overtopping the 

 hydrotlieca-; mesial nematophore very large, robust, projecting at nearly a right angle from the 

 hydrotheca, and free for nearly half its length; there are two cauline nematophores on the front 

 of each internode of the stem, one being a rounded projection on the base of the hydrocladimn. 



Gonosomi'. Oorbula exceedingly thin and transparent, very large and ornate, with twelve to 

 twenty-five pairs of broad leaves, each of which is greatly expanded, the front edge extending 

 forward and upward over the base of the preceding leaf and armed with a row of nematophores 

 from each of which a fine ridge extends directly toward the inner edge of the leaf. The 

 mature (?) corbula seen in some of the smaller specimens is more or less open, and shows that 

 each leaf has both edges armed with rows of nematophores. There are about four more or less 

 modified hydrotheca' between the corbula and the stein. 



Distribution. OS Key West, Florida ; depth, f>i fathoms, State University of Iowa Expedition. 

 Oft' Marco, Florida, 2 fathoms (Henry Ilemphill). 



This is a very distinct and beautiful species in both its trophosome and gonosome. It is of a 

 more delicate texture than any other Plumularian that I have seen. Not only the hydrotheca, 

 but the stem and corbuhe are very difficult to preserve, and especially to mount for microscopical 

 examination. The corbula is the most exquisitely beautiful structure of its kind that I have ever 

 seen, reminding one of the most delicate and intricate designs in spun glass. It is perfectly 

 transparent, and the broad expanded leaves edged with nematophores and ornamented with the 

 fine white lines described above give a delicacy and grace which defies description. 



Type slides. Oat. No. 18050, U.S.N.M.; Oat. No. 15358, Mus. State Univ. Iowa; also in the 

 collection of the author. 



AGLAOPHENIA MINUTA Fewkes. 

 (Pla.te XXI, figs. 1-3.) 



Aylanphenlu minnta FKWKKS, Bull. Mus. Corap. Zool., 1881, VIII, No. 7, p. 132. 

 ia late-carinuta ALLMAK, Journ. Linu. Soc., Zool., 1885, XIX, p. 151. 



Trophosome. Colony nnbranched, springing from a regularly annulated creeping rootstalk, 

 and attaining a height of : [ ! inch, but usually not more than > t inch; stem not fascicled, with 

 two or three deep, oblique nodes near its base, the remainder being divided into regular 

 internodes, each of which bears a hydrocladimn on a strong process from near its distal end. 

 This process bears two strong nematophores on its outer and lower side; hydrocladia divided 

 into short internodes, each of which has two internal thickened ridges, one opposite the 

 iutrathecal ridge and the other below the base of the supracalycine nematophores; nodes 

 very deep. Ilydrotheca' deep, obconic at the base, somewhat swollen mesially and with the 

 aperture not expanded; marginal teeth nine, sharp and deeply cut; a broad anterior keel 

 running from above the mesial nematophore to the margin; intrathecal ridge well marked, 

 oblique, extending around the hydrotheca; supracalyciiie uematophores small, geuiculate, iiot 



