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This conclusion was based upon preliminary cheese curd tests made at Madison, Wisconsin, August, 1894, and duplicated at Fargo in October, and finally upon qualitative analysis made during a period of three winter months, with ten different milch cows under consideration.
The point to be reported upon, at this time, is that of the constancy of species as found : (a) for the same cow for a given length of time; (b) in the same teat of the same cow; and (c) as to whether species are common to different cows or not upon same dates.
In general, the evidence of the work associated with the last named report, was to the effect that there is no evidence that germs are of any certainty common to different animals upon the same date under like conditions ; but that a certain inhabitant of the udder of the same animal may remain quite constant. Thus while only one species, number 30, was observed to be present in more than two animals of the original ten animal test upon different dates, several different species were found to occur at several dates in the same udder.
Commencing July 1st, three animals were placed under cultural investigation, number 24 of which was an animal of the original ten, also number 21. Cultures were attempted from each teat upon gelatine and agar, as often as the work could be handled, the same methods of procuring milk being used as in the previous work, except in the different tests of the same animal, the milk tube or trochar, was inserted different depths. Some sixty of these distinct milkings were taken upon fifteen different dates, during which time the cows ran upon a clean pasture during the day, being housed at night. The milk samples were taken sometimes in the morning and sometimes at night. In all, thirty-seven different species of bacteria were separated ; and, as in past work, were found to be of various physiological types, gelatine liquifiers, non-liquifiers, solid curd types, peptonizing forms, acid and alkali curdlers, etc., including bacilli, micrococci of various forms, and a streptococcus. Thus it may be said that, in general, forms collected are miscellaneous.
Results: Again, there is no marked evidence that species are common among different animals, but there is strong evi. dence of constancy of appearance of certain types when once present. This, perhaps, is to be expected, for it is hardly possible that in an ordinary milking all individuals could be excluded from the milk cistern and lower teat passages.
The following table and annotations may help to show the bearings of the work:
*Expr. No. 1, July 2nd. Nos. 1 Nos. 1 Nos. 1 Nos. 5 Expr. No. 2, July 3rd.
1 9 and 10 5, 100 & 77 Expr. No. 3, July 4th. 16
15 (Not taken) Expr. No. 4, July 6th. (Not taken) 17 and 1
20 Expr. No. 5, July 8th. (Lost Cul.) 23
26, 27, 15, 29 Expr. No. 6, July 10th. 30, 1 (Lost)
31 (Not taken) Expr. No. 10, July 17th. 58, 53, 1
66, 20, 15, 1 Expr. No:13, July 23rd. 96, 93, 94
20, 11, 100, 1 Expr. No. 15, July 28th. 77, 67 (Not taken) | 66, 100 & 67 | 67, 1
*The numbers in each columns--1, 2, 3 and 4 = the laboratory numbers given the different species.
Annotation No. 1, a solid curd, lactic acid forming micrococcus, is seen to be present upon every date, appearing in teat No. 2 upon all possible dates save one.
Nos. 5, 10, 15, 61 and 67 occurred twice each, the intervening days being respectively 2, 8, 7, 4 and 4. It is worthy of note that with the exception of No. 67, each of these was found each time in the same teat.
Cow No. 21
Species present, per teat, by dates.
Expr. No. 8, July 12th. Nos. 45 Nos. 31
31, 50 Expr. No. 12, July 16th.l 53, 51, & 56 | 31, 45
31 Nos. 20 29, 53 55, 56, 57,& 31 (Not taken) | (Lost)
Annotations : With this animal it is to be noted that No. 31, a lactic acid forming micrococcus, is constant to all dates, and upon each date was found present in teat No. 2.
Other germs found twice each were Nos. 45, 53 and 56; but each time in a different teat.
In these three milkings from cow No. 26, the common species to each date are seen to be Nos. 33 and 67. Out of eleven milk samples taken No. 33 occurs in the cultures nine times. The intervening dates being 16,6 and 22 days apart. No. 33 is a streptococcus and in these distant tests, as to time separation, is a strong argument of constancy of presence being possible to an individual species. In growth characteristics this germ is almost a strict anaerobe.
Studying these tables, we find for each animal the following numbered germs present:
Cow No. 24.–Nos. 1, 5, 6, 9, 10, 100, 77, 15, 16, 17, 20, 23, 61, 26, 27, 29, 30, 31, 58, 53, 66, 96, 93, 94, 97,11 and 67, a total of twenty-seven distinct forms.
Cow No. 21.–Nos. 45, 31, 27, 20, 50, 29, 53, 55, 56, 57 and 51, a total of eleven.
Cow No. 26.—Nos. 33, 1, 39, 61, 67, 17, 44, 66, 100, 15, 53 and 77, a total of twelve.
The forms common to three animals equal only one, No. 53, while those common to two of them are seen to be Nos. 1, 100, 77, 15, 61, 29, 31, 66, 67, 29 and 20; eleven constant forms.
General Annotations : From these summaries it is to be noted that cow No. 24 from nine different milkings furnished twenty-seven of the thirty seven germs of the three tests, cow No. 21 six and cow No. 26 four. The numbered germs from the last named animals are representative of but three milking dates each. It is thus a possibility, that further milking dates for these cows might have given others of those common to cow No. 24.
While this point last named, is probably a correct consideration, it is nevertheless quite clearly indicated that the great majority of germs are but incidental in a given udder or teat to the date, perhaps, to the environments of the animal. There are, however, certain few germs found which when once present in a teat or udder, remain with marked presistence. For this capability, these are found to possess what are presumably the proper physiological functions or requirements, as for example, capability to properly thrive in or withstand the normal temperature of the animal's body, and anaerobic or semi-anaerobic faculties.
As in the case of the paper previously mentioned, this is given not as final evidence to convince upon the points mentioned or suggested, but rather as a record of preliminary work accomplished.
Again, an interesting fact is the comparatively low number of species per milk sample. In the first work, winter collections, the range was from one to four species, in this it is one to five with a rather high average number. It is also interesting, though perhaps to be expected, that quantitative determinations vary from low to high numbers for different milkings, very much in accord to these last named figures.
North Dakota Experiment Station, Fargo, N. D., August, 20, 1895.
LIFE BEFORE FOSSILS.
BY CHARLES MORRIS.
The beginning of life upon the earth is one of those mysteries which, to judge from what we now know about it, seems likely never to be solved by ascertained facts. There are modern facts, indeed, which bear upon it, but few geological ones, and none of absolute force. If we leave out of the question the highly problematical “Eozoon Canadense,” we find the first known fossils at a comparatively high level in the rocks; and these, instead of being, as the theory of evolution requires, of very simple organization, are of a degree of development which indicates a very long period of preceding life existence. This primeval fauna, indeed, contains representatives of every branch of animal life except the vertebrate, and these not in their simplest stage, but already divided into their principal orders: the Coelenterate class, for instance, yielding examples of Actinozoa and Hydrozoa; the Crustacean, of Trilobites and Phyllopods; and the Molluscan, of Gasteropods, Lamellibranchs and Pteropods.
This is the beginning of life as we know it. It is very far from the beginning of life as evolution demands, or as the character of the rock strata indicates. Below the Lower Cambrian beds, which contain these fossils, lie several miles of stratified rocks similar in physical character to those above them, and indicating, as Darwin says, “that during a preceding era as long as, or probably far longer than, the whole interval from the Cambrian age to the present day. .. the world swarmed with living creatures.”
Evidently we are not yet at the origin of life. We are miles away from it probably-miles of rock strata, that is. "Between the simplest known microscopic creatures and the much developed Cambrian fossils an immense gap extends. The gap, for example, between a diatom and an oyster is one that represents ages of evolution ; yet it is much less in extent than the yawning gap which we find dividing the line of primeval life, and which geologists have sought in vain to fill. Believers in evolution—who represent about all living scientists and the bulk of living thinkers—cannot but stand in some dismay before this strange circumstance, which must be proved away or explained away before their theory can be fully substantiated. Yet proof is not forthcoming, and only attempts at explanation