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himself, after I had taught him by carrying him around upon my finger and placing him up close to any fly or gnat I found perched upon the wall of the tent. When fully grown he passed most of the day sitting upon the top of the tents, occasionally darting after a passing insect, or, if the weather was particularly warm, perching upon the edge of the table, or any suitable place, under the "fly" of the tent, in the shade.

Once, when starting on horseback up the mountains after birds, at about one hundred yards from camp, I was surprised to hear Chippy coming towards me, playfully twittering, when he alighted upon my shoulder and accompanied me up the cañon. Occasionally he would leave me to catch a butterfly or other insect, upon securing which he immediately returned, alighting upon my hat, against which he beat the captive until in a condition to be swallowed. Frequently on seeing other birds of his species, he would join them, and after sporting with them awhile return to his seat upon the pummel of the saddle, my shoulder or hat, his playmates following to within a few yards, when they would stop, and perching upon a dead branch curiously watch us, wondering probably why their little friend was so fearless of me. Chippy accompanied me thus some three or four miles from camp. Having proceeded as far up the cañon as possible, I there tied and unsaddled my horse; the sun being very hot,

; and the bird disposed to be inactive, I placed him in the shade of my saddle. I then climbed up the hillside over the rocks, until out of sight of my horse, on my way occasionally shooting a bird, and wandering some distance from where I left Chippy ; but upon my return I found him following after me, having discovered my absence by the report of my gun, and started in search of me. We then returned to camp as we had left it.

Our pet bird soon began to attract others of his species to the camp which became quite familiar. They could not, however, persuade Chippy to leave us, he evidently preferring our society to theirs. He was at first perfectly unmindful of the report of a gun, even sitting upon my shoulder when I fired, or often perching upon the gun-barrel when I carried him with me in my rambles. One day, however, wishing to secure one of these flycatchers which flew about our camp, and intending if possible to drive them away, I shot at one of three which were sporting together in the air, thinking that Chippy was sitting upon the tent; fortunately I missed the bird I shot at, which proved to be our pet, he flying in great consternation to the camp, having probably been touched by one of the shot, although not at all injured. His disregard for a gún was now at an end, and the mere picking up of this instrument of death was sufficient to cause his immediate retreat, retiring with terror depicted upon his countenance, the feathers lying close to his body, his crest elevated and neck outstretched, removing to another perch each time I advanced. The moment, however, I laid the gun aside, all his fears were over, and upon approaching him, when I reached out my hand he would hop upon my finger with perfect confidence. Although I might carry him in this way all about the camp, if I approached the gun, which leaned against the tent, he made a precipitate retreat.

We carried Chippy with us, from camp to camp, for nearly two months longer. Everywhere we went he excited the curiosity and wonder of all persons, the Indians included, and we had not the least fear of losing him. One morning, however, in the latter part of September, we missed his familiar awakening twitter, and when we arose from our blankets he could not be found. Search was made throughout the day but without success, and a large hawk having been seen early in the morning hovering about the camp seemed to explain the cause of his disappearance. He was never afterwards seen.

WHAT IS A DESMID ?

BY PROF. ARTHUR MEAD EDWARDS.

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In the language of science, as put upon paper by one of its most zealous devotees, Desmids, or as they are more correctly designated, Desmidiaceæ, are "fresh-water, figured, mucous and microscopic algæ, of a green color.” This author also tells us in similar language that the characteristics of these fresh-water forms are "transverse division mostly complete, but in some genera incomplete. Cells or joints of two symmetrical valves, the junction always marked by the division of the endochrome, often also by a constriction. Sporangia formed by the coupling of the cells and union of their contents."

We have here then, in brief, what a Desmid is, and now let us see if we can make this very concise, scientific and correct definition and reply to our question, plain to unscientific minds.

The difficulties attendant upon the study of these Desmids have perhaps, tended to frighten away even professed naturalists from a field of enquiry teening with promise of results of the greatest interest and profit. At least then we have arrived at the knowledge of one fact, and that is, that a Desmid is a plant, or a member of the vegetable kingdom. This point, it is true, is all but universally acknowledged by every one who pretends to any acquaintance whatever with these creations, and therefore for the time being we will take it for granted that such is the case. In fact it is true that there is no one essential point in which they differ from the other minute plants which have been included under the designation of Protophytes; this name having been applied to them on account of the simplicity of their structure, ranking them as first plants in the vegetable system. But, although the name Protophyte was first bestowed for this AMER. NATURALIST, VOL. III. 40

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reason alone, there seems to be good grounds for supposing that it has been very aptly applied, for naturalists are strongly of opinion that the first forms of vegetable life which made their appearance upon the surface of the globe belonged to this group, and we see them at the present day occurring as the harbingers of more complex plants in pools and ponds, on rocks and by road-sides. The amount of study that has been bestowed upon the Desmids is really very great, but it has been by a special class of observers who have been in the habit of not trusting to the revelations of their umassisted eyes, but have called in the aid of all the contrivances of modern mechanical skill as embodied in that perfect instrument of research, the achromatic microscope. By such students we are assured that in no respect do they really approach the animal kingdom. Many arguments, it is true, have been from time to time advanced in support of their animal affinities, but these have all been determined, now that their life history and that of many other undoubted and undisputed plants have been better understood, to be but strongly indicative of their vegetable nature. But the very fact that for a long time they continued to be bandied from one kingdom to the other, now plants and then animals, only to become plants again, indicates the difficulties attendant upon their study, and the uncertain tenure with which they, even now, hold the position they by courtesy are permitted to occupy.

Ehrenberg, the great German microscopist, asserted that one of the Desmids, known by the name of Closterium, possesses true organs of motion, which it protrudes through apertures in its extremities, and keeps in continual action. Unfortunately, however, more recent investigation has revealed the fact that this statement is wanting in accuracy. No such organs of propulsion are to be seen now that we are possessed of much better microscopes than the Prussian philosopher was wont to use, therefore we can but ascribe the "feet” of his Closterium to defective methods

of observation. Many if not all of the Desmids, it is true, possess the extraordinary power of slowly changing their place, so that in time, varying with the particular forms observed, they approach the side of the bottle in which they are enclosed, upon which the most light shines, and not only so, but many appear to have a continual but steady progressive mode of motion, as when viewed by means of the microscope they are observed to traverse the field of view under the eye of the observer. Yet it cannot be said that this faculty allies them to animals, for not only do the seeds and similar parts of many plants move about in an extremely vigorous manner, but many undoubted Protophytes do so likewise. Motion is not and cannot at the present day be considered as indicative of aught else but change, physical or chemical, else might a grain of gum-camphor darting about upon the surface of a glass of water, be classed among vital organisms.

Doubtless many persons who see the question placed at the head of this article have noticed some bright pool of fresh water, by the road-side or in a field, upon a spring or summer's day, and observed that it was either filled with a seemingly gelatinous mass of light green matter, or had patches of darker green floating upon its surface. This was an indication that Protophytes or simple plants were present, and, although there are chances that such an accumulation or vegetation contains, or even entirely consists of, other organisms, yet in a number of cases hardly anything but Desmids will be there found. To collect these little wonders we have various methods suited to their mode of occurrence, and it will be well to indicate them.

First, then, they are inhabitants of fresh water, and in fact of the freshest kind of water only, decaying animal matter which would cause the water to become foul, even in a very slight degree, being sufficient to kill these tender plants and cause them to be replaced by forms of much greater simplicity. Certain brackish and marine organisms, which were

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