EECEEATIVE SCIENCE. 



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sent some affinities with those of the higher 

 animals. They exhibit a division of the 

 sexes, but whether the husbands and wives 

 cherish sentiments of affection is unknown ; 

 and, notwithstanding the cleverness of their 

 motions, and the possession of a nervous 

 system, their understanding is probably of a 

 very limited capacity. 



The males are much less often found than 

 the females, from which they differ con- 

 siderably — facts which may account for their 

 having been unknown up to a very recent 

 period. Mr. Gosse, who has devoted great 

 attention to this subject, speaks of the " ab- 

 solute and universal atrophy of the digestive 

 system in male Rotifera." He adds, " the 

 duration of life in the male is always very 

 brief. I have never been able to preserve 

 one alive for twenty-four hours." Their 

 functions are soon performed ; " hence we 

 can understand the lack of the nutritive 

 organism." 



A sketch is appended of the mouth or 

 gizzard of the Notommata clavulata, from a 



Jlouth or Gizzai-d (maslax) of Notommata clavulata. — 

 A, hammers {jnallci), each divided into a handle 

 (manubrium), and a hook (uncus) ; B, the anvil 

 (incus), formed of two portions moving laterally, 

 called branches (rami), and a, fulcrum. — Gosse. 



drawing of Mr. Gosse, published in the 

 " Philosophical Transactions," and which will 

 serve to explain this curious organ, the pre- 

 cise structure of which differs in each species, 

 although the principle is usually the same 

 — that of teethed hammers tearing up th§ 

 food. 



We might fill a volume about the Eotifers, 

 but the Vorticellse are waiting, and we must 

 turn our attention to these elegant flower- 

 like, cup-shaped bodies, with fringes of vi- 

 brating cilia, and the slender stalks from 

 which they seem to grow, and which they 

 contract and dart out with an energetic mo- 

 tion. The Vorticella family is far below the 

 Eotifers in natural-history dignity, but they 

 afford some of the most beautiful objects for 

 the microscope, and are physiologically re- 

 markable for the changes 

 which they undergo. At 

 a certain stage of their 

 existence they leave their 

 stalk, and become " en- 

 cysted," as it is called— 

 that is, they envelope 

 themselves in a bag. 

 They also appear in what 



are called acineta and '^°'^'^^^®^* ™^"'°'*°™"' 

 . , - the encysted animal 



achnophrys lorms, with protruding through 

 star-like rays projecting a supposed rupture 

 from their disc. Our of the tunic 

 bottles contained Vorticellae with and with- 

 out stalks, some solitary, and others grow- 

 ing in groups. A fine specimen in the 

 stalkless state afforded much amusement. 

 After viewing him with a power of 100 linear, 

 in the ordinary way, by light transmitted from 

 the mirror beneath the stage, we moved the 

 live-box by means of the revolving plate at- 

 tached to the stage, so as to bring his circle 

 of cilia on the right hand, and in a vertical 

 position. Then, throwing a bright light upon 

 the mirror, and turning it so as to reflect a 

 very slanting pencil of rays through the body 

 of the creature, a very charming sight ap- 

 peared. By this arrangement no light 

 reached the eye except what had passed 

 through the Vorticella, which, so lit up, looked 

 like a luminous cup formed of pearls and co- 

 loured gems, standing on a black ground. 

 As each cilium moved, its bright surface 

 flashed in the light for a fraction of a second, 

 like a sabre glancing in the sunshine, and 



