NOCTILUCA — ANTHOZOA. 471 



tubular prolongations pass oft" beneath the ciliated bands, very 

 much as in the true Beroe (b). In addition to the rows of cilia, 

 the Cydippe is furnished with a pair of locomotive organs of a 

 very peculiar kind ; these are long tendril-like filaments, arising 

 from the bottom of a pair of cavities in the posterior part of 

 the body, and furnished with lateral branches (a) ; within these 

 cavities they are often doubled up, so as not to be visible exter- 

 nally ; and when they are ejected, which often happens quite 

 suddenly, the main filaments first come forth, and the lateral 

 tendrils subsequently uncoil themselves, to be drawn in again 

 and packed up within the cavities, with almost equal suddenness. 

 The liveliness of this little creature, which may sometimes be 

 collected in large quantities at once by the muslin net, renders 

 it a most beautiful subject for observation when due scope is 

 given to its movements ; but for the sake of microscopic exami- 

 nation, it is of course necessary to confine these. Various 

 species of true Beroe, some of them even attaining the size of 

 a small lemon, are occasionally to be met with on our coasts ; 

 in all of which the movements of the body are effected by the 

 like agency of cilia, arranged in meridional bands. Very dif- 

 ferent, however, is the structure of another little globular jelly- 

 like animal, the Noctiluca miliaris (Fig. 229), to which the 

 difliused luminosity of the sea, a beauti- 

 ful phenomenon that is of very frequent Fm. 229. 

 occurrence on our shores, is chiefly at- 

 tributable. This animal is just large 

 enough to be discerned by the naked 

 eye, when the water in which it may be 

 swimming is contained in a glass jar 

 exposed to the light ; and a tail-like 

 appendage, marked with transverse 

 rings, which is employed by the ani- 

 mal as an instrument of locomotion, 

 "both for swimming and for pushing, Nocuivm mumns. 

 may also be observed with a hand- 

 glass. Near the point of its implantation in the body, is a de- 

 finite mouth, on one side of which a projecting tooth has been 

 seen by Mr. Huxley ; and this mouth leads through a sort of 

 oesophagus, into a large irregular cavity, apparently channelled 

 out in the jelly-like substance of the body, and therefore con- 

 sidered by some in the light of a mere "vacuole," though by 

 Mr. Huxley it is considered to possess regular walls ; whilst from 

 its cavity there passes forth a prolongation, which leads, in his 

 belief, to a distinct anal orifice.' The external coat is denser 

 than the contained sareode; and the former sends thread-like 

 prolongations through the latter, so as to divide the entire body 

 into irregular chambers, in some of which "vacuoles" are fre- 



' "Quart. Journ. of Mioroso. Science," vol. iii, p. 49; see also pp. 102, 199. 



