HALOrOL'DYLK ('(lOl'KRI. 81 



EXPLANATION OF PLATE IX, 



Illustrating Dr. Ernest Warren's paper "On Halocordylo 

 cooperi sp. nov., a Hydroid from the Natal Coast." 



Fig. 1. — H. cooperi ; natural size, showing three main stems arising 

 from the Itranched hydrorhiza. 



Fig. 2. — x 7. Small portion of frond, with an internodal group of 

 annulations (/. a.). 



Fig. 3. — x 15. Primary branch with hydranths bearing female 

 gonophores, arising just above the verticil of filiform tentacles. The 

 capitate tentacles are in two alternating whorls. 



Fig. 4. — X 50. Female gonophores in longitudinal section in various 

 stages of development, e. u. is the ectodei'm from which the generative 

 epithelium and ectodei'm lining umln-ella cavity originate. 



Fig. 5. — X 50. Female gonophore in transverse section, showing 

 absence of endodermal lamella l>etween the radial canals. 



Fig. 6. — x 75. Longitudinal section of hydranth, showing its 

 general histological character and the perisarc-groove (j5. </.). 



Fig. 7. — X 75. Growing point of hydrorhiza, showing the epithe- 

 lium secreting the perisarc {p.s. e.), and the naked terminal portion of 

 ccenosarc (h. c). 



Explanation of Reference Letters. 



b. c. Cells of basal endodermal epithelium, c. e. c. Covering endo- 

 dermal cells, c. m. Closed mouth, d. c. Digestive cavity, e. Endoderm. 

 e. u. Ectoderm of umbrella (including germinal epithelium) in gono- 

 phore bud. e. e. External ectoderm of unilirella cavity. (/. e. Generative 

 epithelium, g.e.c. Glandular endodermal cells, y. m. Gelatinous mass 

 (?) at termination of radial canal, h. e. Hypostomal endoderm. i. a. 

 Interaodal annulation. l.n. Large nematocyst. m. Mouth. >m..s. Main 

 stem. n.c. Naked ccenosarc. o.e. Ordinary ectoderm. o.m. Open 

 funnel-shaped mouth. j9. b. Primary tiranch. p. Perisarc. jj. g. Peri- 

 sarc-groove. p. s. e. Perisarc-secreting ectoderm. r. Pamulus or 

 secondary branch. /•. c. Radial canal, s. Spadix or maniilirium. ,s. e. 

 Septate endoderm of tentacle. *•. n. Small nematocyst. u. c. Umbrella 

 cavity, v. c. Vacuolated deeply staining cells of hypostome and t>asal 

 , epitheliiun. 



VOL. 1, PART 1. 6 



