246 



THE POPULAR SCIENCE MONTHLY. 



one of these hairy terrapins, and upon that 

 occasion a correspondent, ' A. B.,' kindly 

 sent me the following note : ' In the " Trav- 

 els of a Pioneer of Commerce in Pigtail and 

 Petticoats," by T. T. Cooper (London, Mur- 

 ray, 18*71, page 459), there is a plate of one 

 of these hairy tortoises from the lakes of 

 Ha-su, above Hankow. These curious little. 



animals were about two inches long, and 

 covered on the back with a long confervoid 

 growth resembling hair. The tortoise being 

 a sacred emblem in China, the Chinese make 

 pets of the hairy tortoise, which they keep 

 in basins of water during the summer 

 months, and bury in sand during the winter. 

 A small lake in the province of Kiang-su is 



The Hairy Water-Tortoise. 



famous for these so-called hairy tortoises, 

 and many persons earn a livelihood by the 

 sale of these curious little pets. The figure 

 in Mr. Cooper's book looks like an oval 

 door-mat with a tortoise-head sticking out 

 at one end.' 



" I have been to the British Museum to 

 see if I could find anything like this hairy 

 terrapin, but could not do so. I shall take 

 the liberty of forwarding this article to his 

 Excellency the Chinese embassador, who, I 

 have no doubt, with his usual kindness, will 

 obtain some further information about this 

 great curiosity." 



Splder-Arfhitectnre. — The snare of the 

 basilica spider would form an interesting 

 object of study for the architect. In it he 

 will find many a difficult problem of con- 

 structive science happily solved, and it may 

 be derive useful hints to guide him in 

 the construction of more substantial edi- 

 fices. As described in the " Proceedings of 

 the Academy of Natural Sciences," of Phil- 

 adelphia, by Rev. H. C. McCook, who has 

 studied Epe'ira basilica among the hills of 

 the Colorado River, Texas, the snare of this 



spider is of composite structure, consisting 

 of a pyramid of M^eb, within which, near its 

 base, is suspended a dome of the same ma- 

 terial, and hanging beneath the open bot- 

 tom of the dome is an horizontal sheet of 

 cobweb. The structure is illustrated in Mr. 

 McCook's paper, and the general effect will 

 be understood if the reader will imagine a 

 pyramidal tent of netting, inclosing a spread 

 umbrella, with a screen of web suspended 

 by coi'ds from the inside of the umbrella 

 and the tips of the ribs. The whole struct- 

 ure is usually suspended from a bush, and 

 thoroughly steadied and its form perfectly 

 preserved by means of silken guys. The 

 meshes of the pyramid are irregular and 

 very open ; the sheet under the dome is 

 also of irregular structure, but the dome 

 is constructed of a vast number of radii 

 crossed at regular intervals by concentrics, 

 after the manner of the snare of the com- 

 mon orb-weaving garden-spider. At the 

 bottom of the dome the radii are about 

 one-sixteenth of an inch apart, and the con- 

 centrics extend entirely and with equal regu- 

 larity to the summit, the meshes much re- 

 sembling those of a fisher's net. The diam- 



