Apkil 1, 1869.] 



HARDWICKE'S SCIENCE-GOSSIP. 



83 



him at the gates of the New "World, to strew his 

 path, as it were, with flowers of the ocean, to hail 

 the triumph of its conqueror and its king. This 

 simple weed opened to me a new domain — the vast 

 world of chemistry. 



I put some of the weed in a bottle of fresh water, 

 to compare it with that brought from the West 

 Indies. It had been there about a fortnight, when 

 I noticed a great change in the water, from a 

 colourless state to a hyacinthine violet, resembling 

 the modern magenta; and I have since thought 

 that a reaction had takeu place similar to that which 

 occurs during the formation of a litmus, cudbear, or 

 archil. 



My female friends at once exclaimed that I had 

 rediscovered the purple of Tyre. I dipped dolls' 

 clothes of different materials in the dye, to which I 

 added a small proportion of soda and alum; calico 

 which I stained with it appeared of a bright purple- 

 red colour, which it retained for years. — From 

 " Tommy Try," by C. 0. Groom Napier. 



EPISTYLIS. 



HAVE found the species of Epistylis here 

 -*- figured of frequent occurrence upon Cyclops 

 quadricornis ; upon which it multiplies to so great 

 an extent as materially to interfere with its progress 

 through the water, appearing to the naked eye as a 

 little cloudy mass about the Cyclops. It consists of 

 a great number of vorticella-like bodies attached to 

 a many-branched transparent pedicle. The indivi- 

 dual animals are frequently so crowded, and in such 

 constant motion, that it is difficult to make out 

 their structure. In the figure only a few are repre- 

 sented, for the sake of clearness. As in Vorticella, 

 a fringe of cilia surrounds their mouths, the course 

 of which on one side is bent into a little hollow, out 

 of which such things as the animal rejects as unfit 

 for food are driven by the strong current produced 

 by the action of the cilia. 



Those things which are selected for food (with a 

 rapidity of choice which is exceedingly wonderful) 

 are gathered into a vacant place immediately below 

 the mouth (e), from which they quickly pass into 

 other parts of the body, and are gradually dissolved 

 and absorbed. W r hen they are fed with indigo or 

 lake, the particles are greedily devoured, and 

 appear as very dark blue or bright red fusiform 

 spots in the body. When the animal is disturbed, 

 the fringe of cilia is withdrawn into the body (b, d), 

 but it is quickly protruded again, the lip, as it were, 

 turning back in order to allow the ciliary motion to 

 proceed without hinderance. The integument of the 

 body is striped with very minute transverse wrinkles, 

 but this structure can only be well seen when the 

 creature is sufficiently still to allow of careful 

 focussing, or happens to come exactly into focus. 

 The body contains granular matter and a vacuole, 

 as in Vorticella, which occurs a little below the 



mouth, and which appears and disappears with a 

 certain amount of regularity. It is a question 

 whether this disappearance arises from the motion 

 of the animal, by which the vacuole is thrown out 

 of focus, or whether it results from the closing to- 

 gether of the sides of the vacuole. It seems to me 

 that the disappearance arises from thellatter cause ; 

 for when the vacuole has disappeared, no change of 

 focus will cause it to reappear ; which, of course, 

 would occur if the vacuole were there. And when 

 the vacuole is in sight, and the focus is altered, it 

 does not disappear, but remains as a blurred spot. 

 It appears to me that the edges close together, for 

 the definition remains sharp up to the moment of 

 disappearance. 



Fig. 54. Epistylis, x 23S. 



The individual animals are readily detached from 

 the pedicle (/, g), and swim about by means of their 

 cilia, seeking some unfortunate Cyclops upon which 

 to settle and found a new colony. Single animals 

 occur attached to such ; aud it is apparently by the 

 longitudinal division of the body and a portion of 

 the pedicle, that the one animal becomes at length a 

 large colony. In one of the animals when free I 

 have noticed a peculiar spiral formation or nucleus 

 (/). They occur in the Podophrya stage (fig. li), a 

 condition of still life through which many of the 

 family of Vorticellina seem to pass. 



J. S. Tute. 



