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SCIENTIFIC NEAVS. 



[April 13, 1888. 



more startling fact has been recently brought to light by 

 unimpeachable authority that the duckbill lays eggs, an 

 operation hitherto held to be the exclusive prerogative of 

 creatures below the mammalian rank. " All life from 

 the egg" is certainly, and long has been, a scientific 

 axiom, but it has nevertheless been considered, in the 

 case of mammals, to apply to the embryo only, and not 

 to the young when actually brought into the world. Yet 

 the duckbill, most puzzling of contradictions, sets our 

 supposed law of Nature at defiance, and usurps, as it 

 were, the distinctive functions of creatures to which 

 it has been adjudged not to belong. The eggs are 

 quickly hatched, it is true, but still as eggs they are 

 laid ; how are we to overcome the ' testimony of this 

 fact ? 



"The essential character," says a well-known authority, 

 " whereby the class of mammals is distinguished from all 

 others is that the creatures composing it bring forth 

 living young, which they suckle, and thus nourish for a 

 time with their milk." But the duckbill, as we have 

 seen, does not bring forth living young, although it un- 

 doubtedly nourishes its offspring, when they leave the 

 protecting egg-shell, with its milk. Are we, then, to 

 relegate it to the class of the birds ? If so, how is the 

 existence of mammary glands and teats to be accounted 

 for ? Are we to retain it among the mammals ? If so, 

 how are we to describe the distinguishing features of 

 that group ? Are we to adopt a middle course, and 

 consider it as a connecting link between the two classes ? 

 If so, surely the whole theory of classes vanishes alto- 

 gether, and we can only look upon the animal kingdom 

 as one vast tribe, indivisible into smaller groups of 

 marked and distinctive characters. Mammals, birds, 

 reptiles, fishes, all the old familiar divisions must go, 

 and our system of classification must be entirely reor- 

 ganised, in accordance with facts to whose bearing and 

 importance we can no longer shut our eyes. 



This view of the question is strongly upheld by the 

 discoveries of the last three or four decades. The colugo, 

 or flying lemur, is clearly a connecting link between the 

 monkeys and the bats, and we can no longer regard 

 those so-called orders as truly distinct. The chetah, or 

 hunting leopard, as clearly connects the cats with the 

 dogs. The mud-fish, or lepidosiren, is at least as much 

 a fish as a reptile, and Mr. A.G. Butler has lately proved 

 that there is no real and unvarying distinction which can 

 be relied upon to separate the butterflies from the moths. 

 The Amphioxus, again, is one of the most anomalous of 

 living creatures, being, practically speaking, a vertebrate 

 animal without a skeleton ; and for all that we can tell 

 to the contrary, we may yet meet with some mollusc- 

 like fish, or fish-like mollusc, more strictly intermediate 

 still between the two primary divisions of the animal 

 kingdom. 



Even if it be not now existent, geology may supply us 

 with it, just as it has already supplied the connection be- 

 tween many groups of animals which to-day seem per- 

 fectly distinct. Transitional forms appear always to be 

 physically weak. The colugo is weak, the chetah is 

 weak — comparatively speaking — the duckbill is weak, 

 and the Amphioxus is weak. Hence such forms are 

 more prone to die out, less able to hold their own in the 

 struggle for existence than others possessing in more 

 marked degree the characters of the order to which they 

 belong, and more specially adapted to their surroundings. 

 And hence, consequently, the gaps between classes, 

 ribes, orders, and families are very probably in all cases 



more apparent than real, and in many are certainly 

 bridged over by creatures still existing, or by others 

 which have existed at some more or less remote period 

 in the past. Of the former, the duckbill is undoubtedly 

 our most striking example. It is, as far as any animal 

 can be, exactly midway between two of the most im- 

 portant classes in our present system of classification. 

 And thus it serves, beyond a doubt, to merge the one 

 into the other, and to show us that we have still very 

 much to discover in the field of comparative anatomy. 



For ordinary, every-day employment, our present zoo- 

 logical terms will doubtless live ; considered in their rela- 

 tion to scientific phraseology, they will as certainly 

 perish. Just as we have discarded the nomenclature 

 and the classification of our forefathers, so will our de- 

 scendants discard ours. And it is such discoveries as 

 this concer.'ing the egg-laying propensities of the duck- 

 bill which prove to us beyond a doubt how assuredly our 

 system is doomed. 



[We may here add a fact which, while it tends to 

 separate the duckbill from mammalia, connects it rather 

 with reptiles than with birds : its body has the low tem- 

 perature of 76'8° Fahr., that of the mammalia being on 

 the average 101° Fahr. — Ed. S. A^.] 



A Village of Beavers. — One of the few colonies of 

 beavers to be seen in Europe is that at Amlid, near 

 Christiansand, in Norway. Sometimes a dozen of these 

 animals may be seen at once disporting themselves in 

 the water. Their huts are built at the edge of the 

 stream, and are two stories in height, one above and the 

 other below the water. The walls are made of thick 

 logs, and the roofs of sticks and clay. 'I he beavers 

 have cut down all the aspens in the neighbourhood, 

 and are beginning to attack the birch-trees. They cut 

 trees of more than eighteen inches in diameter off at the 

 base. The branches are dragged down to the water 

 along real roads or slides, which are cleared of any 

 roots which might be in the way. Sentinels are posted 

 to give the alarm in case of danger, when all the beavers 

 take to the water. 



Cunning of the Fox. — Dr. J. F. Landrey, in Popular 

 Science News, relates the following, showing the wonder- 

 ful sagacity of the fox : — On the Lower Wabash a com- 

 pany of hunters from Tippecanoe county encamped for 

 the night among the cavernous limestone hills occa- 

 sionally found in those regions. The hounds soon traced 

 up the retreat of an old gfey fox and her family in one 

 of those narrow crevices that probably led into a more 

 open cavern further in. The whining of the young foxes 

 was very distinct, and led to louder brayings of the 

 hounds. The mother, however, was " not at home." 

 But it was not long before her barking was heard beyond 

 the camp on a small hill in another direction. The 

 dogs soon took the hint, and gave her a magnificent 

 chase around the hill. Doubling on her track, she 

 eluded the dogs, returned to her cubs, and either carried 

 or induced them to follow her into the deeper recesses 

 of the cavern, beyond the dangers of digging and chas- 

 ing. I have often thought that little piece of strategy a 

 masterly piece of generalship. What could be more 

 natural than to desire to draw away from her young 

 ones the threatening dogs and men ? Seeming to know 

 that her own barking would have the desired effect of 

 diverting their attention to larger game in an open field, 

 she ventured to draw their attack upon herself, and 



