Marvels of the Universe 



489 



It has already been related in these pages how the sub-order of 

 the Dinosaurs arose, addicted to a purely ^■egetable diet, and 

 described as " bird-limbed," because they walked mainly on their 

 hind legs, which became very long, and used the shorter fore-limbs 

 for grasping. But a section of these bird-limbed Dinosaurs 

 relapsed into going about on all four legs, and although their 

 hands and arms continued to be a little smaller and shorter than 

 the feet and legs, they grew so thick and substantial as not to 

 exhibit much disproportion. Prominent for its extraordinary 

 appearance amongst these vegetable-eating Dinosaurs of very 

 mammalian appearance was the monster called Triceratops, from 

 the three bony projections or horns growing from the upper sur- 

 face of the skull, one pair just above the eves and a single horn 

 from the top of the nose. There were probably no front teeth, 

 but the fore parts of the upper and low^er jaws were fashioned 

 into something like a hooked beak. But there remained a sub- 

 stantial set of grinding teeth in the back part of both jaws. 



It is quite possible that these extravagant Dinosaurs had ceased 

 to lay eggs, and, like some living reptiles and other extinct forms, 

 had taken to developing the young within the body and giving 

 birth to them fully alive and able to take care of themselves. 

 And no doubt, as occurs with most very specialized forms of 

 vertebrates, the number of young produced at a time mav have become fewer and fewer, until at 

 last the Triceratops, so admirably reproduced in sculptured form by Mr. Pallenberg at Stellingen, 

 may have had only one calf at a time. Through the enterprise of Mr. Hagenbeck, a wonderfully in- 

 teresting group, which we may suppose to be father, mother and baby, of this Horned, Frilled and 

 Armoured Dinosaur, is set forth for exhibition amid very natural surroundings of wood and water. 



J'liolohii] Ui"ll>i •''"'«. /'■•'•''■■. ''■'-■*'• 



THE EGG-CAPSULE OF THE 

 LEAF INSECT. 



The mimicry of this insect is apparent 

 throughout its life-history, while the eggs 

 have all the appearance of ribbed seeds. 

 They are here shown twice natural size. 



LEAF INSECTS 



BY SIR H.\RRY JOH.N'STON, G.C.M.G, 



Mimicry in insects is a subject of vast complexity, deep interest, 

 and one which stiU arouses fierce conflicts of opinion amongst 

 students of natural history. Whether it arises to some e.xtent 

 from the deliberate exercise of wiE power on the part of the insect 

 — which, being conscious of its resemblance, partial or even ex- 

 traordinary, to its surroundings, deliberately makes use of this 

 similarity for purposes of eluding the observation of enemies or 

 disguising itself in order to prey on unsuspecting victims — or 

 whether, on the other hand, the mimicry has been begun and has 

 become perfected by a series of accidents resulting favourably for 

 the species, are points not yet determined as universal articles of 

 faith on the part of biologists. To the observer with a normal 

 mind it would seem to be an inevitable conclusion that these 

 insects, like birds, fish, reptiles and mammals, are completely con- 

 scious of their resemblance in colour or form to their surroundings 

 and make full use of this advantage, deliberately choosing to place 

 themselves where the resemblance may be most effective. When 

 travelling through the forested regions of the Uganda Protectorate 





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J-/mloli»} {IJvgli Mtiin. 



THE 10UNG LEAF INSECT. 



TKe eggs KatcK out into reddish- 

 coloured and active Leaf Insects, who be- 

 come green soon after they begin to feed 

 upon leaves. 'Three times natural size.) 



