Pink Monads and their Enemies. 101 



distinct from other objects much, like them. The colour can- 

 not be taken as a sufficient distinction to mark a species, nor 

 can variation in size, unless both striking and hereditary. 

 My Ohromatia were all rose-pink, but I should not regard 

 them as distinct from violet or brown sorts. They colour 

 mud and other objects at the bottom of ponds. Those I took 

 were only a few inches under water, and the hue is probably 

 affected by the depth at which they grow, and the quantity of 

 light they receive. 



The most active enemies of my pink Monads were the crea- 

 tures represented in Fig. 5. It is quite impossible to represent 

 the delicate structure of these objects in any engraving. The 

 reader must imagine the globular body to be white and transpa- 

 rent ; the little dots inside them represent vesicles obtained from 

 ~the Chromatia, and ingulped by a mouth opening wide and slant- 

 ingly near the filament. Not a vestige of this mouth could be 

 discerned except when it was in the act of opening or shut- 

 ting. No definite internal organs could be discovered in 

 my specimens, but no doubt some existed. The filaments 

 were so delicate and colourless that they could only be seen at 

 favourable moments. The slightest motion which took them 

 out of the exact focus, or the best possible illumination, ren- 

 dered them invisible. The tails were still more delicate, and 

 although both head and tail were frequently seen in the same 

 individual, it was rarely possible to focus both at the same 

 time. Their tails were susceptible of considerable variation 

 by lateral expansion and contraction, and the animals could 

 change from the globular form to a pear shape, or even to 

 the shape depicted in Fig. 6, which represents what may be 

 another species, as it had no tail, and did not become either 

 globular or pear shaped. The most common forms of these 

 animals are represented in Fig. 7. They were very active, 

 swimming freely, squeezing themselves through obstacles, 

 and dashing furiously against the Monads. Sometimes they 

 swallowed a little Monad whole ; but their usual plan was to tug 

 and thump at the big ones until they could get at their contents. 

 The object depicted in Fig. 6 was less common, but appa- 

 rently engaged in the same business. 



Fig. 7 shows an animalcule remarkable for the length of 

 its cilia. It had a conspicuous contractile vesicle and a mouth 

 at the smaller end. It was an active creature, and seemed fond 

 of the Monads in an early stage of their growth. 



In one instance, one of the Fig. 5 objects used his tail as 

 a foot, and sprung up and down from it, but without the jerk 

 of a Vorticellid. 



I have seldom met with prettier objects than the pink 

 Monads and their enemies, and if any of my readers notice a 



