THE MUSEUM. 



53 



then brought the tip of my left thumb 

 betsveen its mandibles. These closed 

 at once on the hard and calloused skin, 

 the tips piercinf^ through and through 

 and meeting beneath the surface. By 

 exerting no little force, during the ex- 

 hibition of which the cervical attach- 

 ments underwent considerable strain, 

 the mandibles were dragged through 

 the skin. Not till then did the creat- 

 ure separate them. 



These members are powerful weap- 

 ons of offense and defense, and one 

 should carefully avoid them when ex- 

 amining this insect Samson. 



The larva or grub of Dynastes is the 

 largest of all the beetle grubs. The 

 individual I have is very near two 

 years old and will pupate during next 

 winter. It will emerge a fully devel- 

 oped rhinoceros beetle about next May 

 or June. When this grub is first 

 hatched out, it is quite active, boring 

 and eating its way through wood that 

 is just beginning to decay. As it 

 grows older, it becomes sluggish and 

 seeks wood that is softer and more de- 

 cayed; finally, just before it pupates, 

 it seeks the rotten dust and broken up 

 detritus of the cavity and there under- 

 goes further metamorphosis. The 

 grub was reared from the egg. 



This giant among beetles is remark- 

 ably strong. After fastening it to the 

 tin cart mentioned elsewhere in this 

 paper, I placed in the little vehicle one 

 ounce of bird shot. The beetle pulled 

 this along without difficulty. I then 

 placed a half ounce more of shot in 

 the cart. This seemed to bring out 

 the strength of the insect, for it bent 

 to its work and clearly showed that it 

 felt the additional weight very mater- 

 ially. .Again I added a half ounce of 

 shot. This seemed at first to bring 

 the load to a weight beyond the creat- 

 ure's strength, but when I goaded it 

 with an electric needle, it "bowed it- 

 self," even as Samson did between the 

 pillars of Dagon, and pulled this, to 

 it, enormous weight of one thousand 

 nine hundred and twenty grains, a 

 measured distance of two inchesi The 



beetle weighed only one iiundred and 

 eight grains; consequently, it moved a 

 weight eighteen times greater than its 

 own. To eijual this feat I would be 

 compelled to drag a wagon and load 

 which together weighed fou'- thousand 

 five hundred pounds! When we take 

 into consideration that two thousand 

 pounds is a heavy load for two strong 

 draught horses, we can appreciate all 

 the more what a wonderful exploit this 

 was. This beetle showed a dynam- 

 ometric strength of three hundred and 

 ten grains for one of its fore legs. 



In order to further test this insect's 

 strength, I gently placed on its back a 

 common paving brick weighing some 

 four or five pounds. The beetle 

 moved this brick perceptibly to and 

 fro. If a man were to be subjected 

 to a like experiment, the brick being 

 as large in proportion to him as it was 

 to the beetle, he would be crushed in- 

 to a shapeless mass. 



Principles of Animal Development 



A Whelk's Egg. 



"Omne vivum ex ovo" is now an 

 ancient aphorism, says Prof. John 

 Beard, of the Edinburg University in 

 February Xatural Science, and it has 

 become a commonplace to say that 

 the starting place of almost all animal 

 development at the present time is the 

 fertilized egg. The phenomena lead- 

 ing up to this need not concern us at 

 present. Let us assume that we have 

 got our fertilized egg, and let us in the 

 first place consider what sort of a thing 

 it is. If the choice of such an egg is 

 given, how great is the variety out of 

 which it may be selected. It may be 

 the microscopically small egg of an 

 Echinoderm, or one of larger size from 

 the cocoon of an earth worm, the still 

 bigger one from the leathery egg-case 

 of a Whelk, or the huge one from the 

 marvellous egg-capsule of a smooth 

 Skate. It may be so large and con- 

 tain so much poor material that the 

 developing organism may feed upon it 

 for two years, or so small and so des- 



viVP^p^Bi^m 



