Hydra. Z. HYDROIDA. 95 



gating- much more abundantly, furnished a good supply of what was 

 evidently a favourite food. 



2. H. VULGARIS, orange-broicn or sometimes oil-green ; body 

 cylindrical ; tentacula 7-12, as long or longer than the body, 



Plate I. 



Polypes de la seconde espece, Tremb. Mem. pi. 1, fig. 2, 5 ; pi. 2. fig. 2 ; 

 pi. 6. fig. 2 and 8; pi. 8. fig. 1—7; pL iO. fig. 1—7 ; pi. 11, 12, 13. 



figs. omn. partly copied in Adams, Micros, 399, pi. 21. fig. 6 Hydra 



vulgaris, Pall. Elench. 30. Ellis in Phil. Trans. Ivii. 430. Ellis and 



Soland. Zooph. 9 H. grisea, Lin. Syst. 1320. Mull. Zool. Dan. 



Prod. 2.30, No. 2784. Verm. i. ii. 14. Ure's Rutherg. 233. Berk. 

 Syn. i. 222. Turt. Gmel. iv. 692. Turt. Brit. Faun. 218. Blumenb. 

 Man. 295. Stew. Elem. ii. 452. Lam. Anim. s. Vert. ii. 60. Bosc, 

 Vers ii. 275. Stark, Elem. ii. 443. Templeton in Mag. Nat. Hist. ix. 



418 — H. brunnea, Templeton, loc. cit. 417. fig. 56 First sort of 



Polype, Baker, Polyp. 17. c. fig L'Hydre commune, Blainv. Acti- 



nol. 495. 

 Hab. Weedy ponds and slowly running waters Probably common 

 in all parts of the kingdom. 



On comparing the descriptions of the authors quoted above, I am 

 led to conclude that this species is either subject to much variety, or 

 that two species have been confounded together, and given rise to a 

 discrepancy which seems otherwise irreconcileable. My own expe- 

 rience inclines me to the latter supposition, but since I have had no 

 opportunities of making observations on specimens from different and 

 distant localities, I deem it more prudent to indicate what appear to 

 be two species as only varieties of the vulgaris, until the point can 

 be settled by more leisured naturalists. 



Var. a. aurantia, light reddish-brown or orange-coloured ; tenta- 

 cula not longer than the body. Fig. 2. 



Var. b. grisea, light olive-green ; tentacula paler and longer than 

 the body. Fig. 1. 



The first is by much the commoner, and does not exceed the H. 

 yiridis in size, which it resembles also in its habits and form. It is 

 always of an orange, brown, or red colour, the intensity ofWie tint 

 depending on the nature of the food, on the state of the creature's 

 repletion, becoming even blood-red when fed upon the small crim- 

 son worms and larvse which usually abound in its haunts.* The ten- 



* " I have found a bright red Hydra rather abundant on Putney Heath, near 

 London. It does not much differ, except in colour, from the green one." J. 

 E.Gray in lit. May 6, 1833 — See Trembley's Mem. p. 47, and 128. 



