HYDATINAD^. 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 from similar points of view. The nervous ganglion has an unusual 

 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 obvious and normal. The young animal quits the egg while yet in 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. 



Bhinops vitrea usually swims at a moderate pace, rolling gentlj round its longer 

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

 as Synchceta 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 Algce, 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 front of the body into a long ciliated tube. 1 



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



Genus NOTOPS, Hudson. 



GEN. CH. Body not conical ; foot long and symmetrically placed with respect to 

 the 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 trophi. They are, however, curiously unlike in their 

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

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

 widely from all the Hydatinadce in the corona and trophi. Feeble, however, as are its 

 affinities 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. BRACHIONUS, Ehrcnberg . 

 (PI. XV. fig. 1.) 



Nutommata Iracliiomts . . . Ehrenberg, Die Infus. 1838, p. 433, Taf. 1. fig. 3. 



Leydig, Ueb. d. Ban d. Raderth., 1854, p. 99. 



Hudson, Man. Micr. J. vol. xiii. 1875, p. 46, pi. xci. figs. 1-4. 



SP. CH. Trunk square ; foot one-third of total length, placed in continuation of 

 the body's longer axis, not wholly retractile; trophi malleate. 



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

 heat frequently 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 N. brachionus there in abundance : 

 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 winds, 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 



1 Dr. Plate (loc. cit.) says that /?. ritrea has but one toe. 1 thought so myself, till I saw the 

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



