HYDATINAD.E. 11 



as an organ of touch. The inner ciliary wreath consists of larger cilia which are some- 

 times held erect. The oesophagus is long and narrow, and the gastric glands so irre- 

 gularly conical, that they generally appear unlike ; probably owing to their being seldom 

 presented to the eye h-om similar points of view. The nervous ganglion has an mrusual 

 position. It lies near the end of the proboscis, and gives off, above, four parallel nerve- 

 threads ; the two outer of which pass to the eyes, and the two inner to the sensitive 

 bare spot on the tip of the proboscis (fig. 2c). The rest of the internal structure is 

 both ob\ious and normal. The young animal qmts the egg while yet m the body of 

 the parent, and may often be seen filling up a large portion of the body-cavity. The 

 ephippial eggs closely resemble those of Conochilus volvox. 



lihinops vitrca usually swuns at a moderate pace, rolling gentlj rol^nd its longer 

 axis as it goes, and every now and then bending back its proboscis, or turning somersaults 

 as Synchata pectinata does, only in a much more leisurely manner. Occasionally it 

 darts forward ; and, at each time that it has done so, I fancied I could see the atom 

 which it wished to secure. Then it glides over the stems of Algm, using its long pro- 

 boscis just as Adineta vaga does its ciliated face ; and, when a larger atom than usual 

 has been drawn into the coronal cavity, it compresses the broad flaps of the corona, 

 and rounds the whole fi-ont of the body into a long ciliated tube.' 



Length, ^i,, inch. Habitat. Chfton (C.T.H.) : not common. 



Genus XOTOPS, Hudson. 



GEN. CH. Body wo< conical; foot long and symmetrically placed tcith respect to 

 tlie trunk, or short and wholly retractile within the ventral surface; eye single, occi- 

 pital. 



Of the three remarkable species contained in this genus, two, N. Brachionus and 

 N. clavulatus, are strikingly alike each other, especially in the head and its ciliated 

 protuberances, and also in the tropin. They are, however, curiously unlike in their 

 outline, and in the relative length of the foot. The third species, K. hyptopus, resembles 

 N. clavulatus hi the short foot, and in the odd position in which it is placed ; but differs 

 widely from all the HydatinadcB m the corona and tropin. Feeble, however, as are its 

 aflfinities with the two other species of the genus, they are stronger than those it has 

 with any other ; so it has been placed here as the best makeshift that could be devised. 



N. BKACHioKus, Ehrenberg. 

 (PI. XV. fig. 1.) 



Kctcmmata brachionus . . . Ehrenberg, Die Infvs. 1838, p. 433, Taf. 1. fig. 3. 



I.eydig, Ueh. d. Bau d. Radcrth., 1854, p. 99. 



..... Hudson, Mon. Mkr. J. vol. xiii. 187.5, p. 46, pi. xci. figs. 1-4. 



SP. CH. TxvjUl square ; foot one-third of total length, lAaced in continuation of 

 the body's longer axis, not u-holly retractile; trophi malleate. 



I found this handsome creatiure in a small rain-pool in Leigh woods. The summer 

 heat h-equently dried the pool up, but a heavy shower or two soon filled it again ; and, 

 two or three days after the downfall, I always found JV. brachionus there in abimdance : 

 no doubt hatched out from eggs .deposited on the rotting leaves which formed the 

 bottom of the pool. These strange habitats of the Eotifera are probably due to their 

 eggs being wafted by wir.ds, or carried by birds ; so that it is no wonder that this species 

 should have been captured by Schmarda in a spring near the top of Adam's Peak in 



' Pr. Plate {loc. cit.) sars that R. vitrca has but one toe. I thought so myself, till I saw the 

 creature, of its own accord, sep.aratc the apparently single toe, into two. 



