312 



Mr. J. Ritchie on a 



where it is much shorter and lies altogether free from the 

 hydrotheca. Neither it nor the supracaljcine nematophores 

 are completely tubular ; their margins are serrate. Each 

 stem-internode bears three nematophores : one posterior, in 

 the angle between internode-process and stem ; the others 

 anterior, one beside the stem-process, the other proximal to it. 

 Tlie supporting tubes of the fascicle bear somewhat smaller 

 nematophores, arranged on each tube in opposite pairs at 

 regular intervals. 



Fiff. 1. 



Fio-. 2. 



Fig. 1.— Hydrotheca of Cladocarpus formosus. x 4-5. 

 Fig. 2. — Hydrotheca of Cladocarpus crenatus, var. aUniani. 



X 45. 



Viewed from the anterior the gonangia are obovate, but in 

 lateral aspect the posterior wall is seen to be arched over the 

 termino-lateral aperture (suggesting the overcurling tip of an 

 oriental slipper), as in the case of C. ventricosus (AUman) *. 



" Cladocarpus formosus " of the * Challenger ' Report. — 

 Comparison of the characters above described with those of 

 the solitary specimen obtained by the ' Challenger' — for the 

 opportunity of examining which I am indebted to Mr. Edgar 

 A. Smith, I.S.O., of the British Museum — shows that 

 Allman's identification is mistaken. For the ' Challenger ' 

 specimen differs in lacking an intrathecal ridge, in possessing 



* See Nutting, C. C, "American Hydroids : I. The Plumularidse," 

 Smithsonian Institution, Special Bulletin, Washington, 1900, pi. xxvi. 



