558 



Marvels of the Universe 



five and six inches, and a height of over three inches. Its flesh, when cooked, has the dehcate 

 flavour of crab. Another curious specimen is the Diadem Barnacle, which burrows into the thick 

 skin of whales or turtles. Its appearance is that of a chalky white tube, with raised rings ; but only 

 the beak is visible, the rest of the animal being embedded in the hide of its host. 



THE LEECH AND ITS BITE 



BY E. J. SPITTA, F.R.M.S. 



The Medicinal Leech, it must be acknowledged, is a repulsive looking animal, but it has an arrange- 

 ment for biting which is at once wonderfully constructed and marvellously adapted to the purpose. 

 It should first be explained that this bite is not a bite at aU in the ordinary acceptation of the 

 word, for it partakes of the nature of a " saw-cut " or, perhaps, it should be more strictly called a 

 combination of three cuts radiating from one centre. This triangular incision is caused by the 



Photo ftu] 

 A portion of the 



[£. /. Spina, F RM.S. 



THE TEETH OF THE LEECH. 



has here been very highly magnified to sho\v the teeth, sharp-pointed and sharp-edged 

 fangs which border the saw. 



simultaneous action of the three so-called tongues — transparent-looking, semicircular bodies — one 

 of which is shown on its side in the illustration on page 557, moderately amplified. If the teeth be 

 very highly magnified upon a dark ground, they appear as in the illustration on this page, and are 

 seen to be sharp-pointed and sharp-edged fangs — like the teeth of a circular saw. Their movement is 

 to and fro, which is effected b\? the muscle upon which each tongue is set. 



LIANAS OR BUSH-ROPES 



The remarkable Lianas illustrated are very familiar objects in tropical forests. Especially note- 

 worthy are they throughout the region of the Cameroons, also in Western Uganda, and in the 

 forests of the Northern and Central Congo. In these districts thej' are the stems and branches of 

 various kinds of Landolphia, a genus of rubber-bearing trees or shrubs, which furnishes nearly aU 

 the wild rubber derived from Africa. The Landolphia genus supphes most of these rubber 

 " vines," so called :because their habit of growth is very like that of a vine. 7 They chmb over the 

 big trees, sometimes to a height of two hundied feet above the ground, hanging occasionally in 



