y 



8 



RANDOM NOTES ON NATURAL HISTORY. 



has come into good repute with the fresh- 

 water angler, and is often, as a whole or in 

 parts, used as a bait for the omnivorous 

 pickerel. It is thus often spolcen of as the 

 Pickerel Frog, an appellation which it has 

 in common with its more elegant congener, 

 Eana halecina. The Marsh Frog often 

 grows to a considerable size, the body 

 alone sometimes measuring three inches in 

 length, while the legs often exceed four 

 inches. 



Vorticella, or the Bell Animalcule. 



In those who have interested themselves 

 in observing the more minute creations of 

 nature, few objects have awakened more 

 admiration or wonder than a colony of 

 these active Protozoans, or single-celled 

 animals. Though a most familiar object, 

 it is quite possible that there are not a few 

 of the younger readers of Random Notes 

 to whom a short description of the manner 

 in which the animal may be captured, and a 

 few words on its structure and habits will 

 not be wholly lost. 



If the weeds and stones of a spring or 

 clear brook be scraped with a fine net, and 

 the result be washed out in a jar of fresh 

 water, in a few days there will be observed, 

 on the sides of the vessel, several white, 

 moss-like growths which sway back and 

 forth as the water is disturbed, but which im- 

 mediately disappear on being touched with 

 some object, as the point of a pencil. If 

 one of these growths be now examined with 

 a hand lens, b}' looking through the side of 

 the jar, there will be observed what strik- 

 ingly resembles a bunch of toy balloons — a 

 colony of vorticellae. Now if the entire 

 bunch be removed from its support, by pass- 

 ing a knife blade beneath it, and placed on 

 a glass slide with a small quantity of water 

 and covered with a thin cover glass, in such 

 a wa}' as to exclude anv large air-bubbles, 

 man}' important points can be made out. 



There will first be noticed a main stem in 

 which is a striated elastic cord, which, by 

 contracting, draws the bunch of vorticellae 

 toward what was once its attachment. The 

 distal end of this stem branches into num- 

 erous sub-divisions, each of which, in struc- 

 ture, resembles the main stem and bears at 

 its extremity a bell-like expansion — the 

 vorticella proper. By watching the con- 



tractions of these stems and branches, it 

 will be noticed that the power of volition 

 seems to reside in each individual, for while 

 one portion of the colony may contract on 

 being irritated, another portion will remain 

 expanded and active. On all being dis- 

 turbed the main stem contracts, drawing 

 the entire colon}' to the surface of the sup- 

 port on which it grows. 



Each bell, in its extended condition, is 

 seen to have a flaring margin which is lined 

 with a row of cilia whose motion induces a 

 fresh current of water to be constantly flow- 

 ing by and among the animals, from which 

 they seize the nutritive particles. 



On viewing the object, a single individ- 

 ual bell, with a higher power, the ciliated 

 margin is seen to be partially covered by a 

 disk, the epistome, which is also along its 

 rim provided with cilia. If the single indi- 

 vidual be now more closely examined, it 

 will be noticed that the disk is raised upon 

 one side and that particles from the water 

 are constantly entering and leaving the or- 

 ganism at this place, the vestibule, which 

 thus functionizes as the mouth. 



Particles once entering the vestibule can 

 be follovved as the}' ar^ taken further and 

 further into the bod}'^ of the animal and fin- 

 ally, having all nutritive matter digested 

 from them, they are thrown out from the 

 same door which they entered. 



If it is desired to further examine the di- 

 gestive apparatus, a simple method is to 

 induce the animal to accept as food some 

 coloring matter, as powdered carmine. 

 This, when being taken into the vestibule, 

 will beautifully illustrate the action of 

 the cilia, and as it fills up the digestive 

 tract, will map out its outline in a most 

 beautiful manner. H. Karey. 



- Immaculate Eggs of Song Sparrows. — 

 An item that interests me is the finding 

 of a set of Song Sparrows ^ in my garden, 

 the eggs being almost entirely without any 

 markings whatever — only one of the set 

 being noticeably spotted ; they closely re- 

 sembled eggs of Blue Bird ; pale bluish 

 tint. — J. N. Clark. ,/ 

 / 



Ninety Geological and Zoological Slides. 

 Original cost 75 cents to $1.00 each. Price 

 for the lot, $30.00. List furnished. Ad- 

 dress A. A. Tenne}', Williamstown, Mass. 



