HARDWICKE'S SCIENCE-GOSSIP. 



37 



racter observed. In order that this structure may- 

 be compared in different genera, I have given 

 figures of three. Eig. IS is taken from Walchen- 

 aera cristata ; fig. 19 is from a larger spider 

 closely allied, called Linyphia confusa ; and fig. 20 

 from Ciniflo similis, both taken at other times, 

 skulking in a similar manner under stones. The 



Fig. ig. Palpus of Linyphia. confusa. 



figures are drawn from specimens mounted in bal" 

 earn, flattened out so as to exhibit structure by 



Fig. 20. Palpus of Ciniflo similis. 



uncoiling the upper portion, which naturally is 

 coiled up compactly like a watch-spring. The pro- 

 jecting hooks and processes are very curious. In- 



dustrious microscopist, with little to do, and want- 

 ing occupation, here is good work for you ! Study 

 a spider well, and then write a monograph, as has 

 already been done for the House-fly. 



With an anecdote of spiders as teachers, taken 

 from the Quarterly Review of a quarter of a century 

 ago, I shall leave them to the better consideration 

 of my readers. Quatremer Disjonval, a Frenchman 

 by birth, was an adjutant-general in Holland, and 

 took an active part on the side of the Dutch patriots 

 when they revolted against the Stadtholder. On 

 the arrival of the Prussian army under the command 

 of the Duke of Brunswick, he was immediately taken, 

 tried, and having been condemned to twenty-five 

 years' imprisonment, was incarcerated in a dungeon 

 at Utrecht, where he remained eight years. During 

 this long confinement, by many curious observations 

 upon his sole companions, spiders, he discovered 

 that they were in the highest degree sensitive of 

 approaching changes in the atmosphere, and that 

 their retirement and reappearance, their weav- 

 ing and general habits were intimately connected 

 with the changes of the weather. In the reading of 

 these living barometers he became wonderfully 

 accurate, so much so, that he could prognosticate 

 the approach of severe weather from ten to fourteen 

 days before it set in, which is proven by the follow- 

 ing remarkable fact which led to his release. When 

 the troops of the French republic overran Holland 

 in the winter of the year 1791, and kept pushing 

 forward over the ice, a sudden and unexpected thaw 

 in the early part of December threatened the de- 

 struction of the whole army unless it was instantly 

 withdrawn. The French generals were thinking 

 seriously of accepting a sum offered by the Dutch, 

 'and withdrawing their troops, when Disjonval, who 

 hoped that the success of the republican army might 

 lead to his release, used every exertion, and at 

 length succeeded in getting a letter conveyed to the 

 French general in 1795, in which he pledged himself, 

 from the peculiar actions of the spiders, of whose 

 movements he was enabled to judge with perfect 

 accuracy, that within fourteen days there would 

 commence a most severe frost, which would make 

 the French masters of all the rivers, and afford them 

 sufficient time to complete and make sure of the 

 conquest they had commenced before it should be 

 followed by a thaw. The commander of the French 

 forces believed his prognostication and persevered. 

 The cold weather which Disjonval had predicted 

 made its appearance in twelve days, and with such 

 intensity that the ice over the rivers and canals 

 became capable of bearing the heaviest artillery. On 

 the 2Sth of January, 1795, the French army entered 

 Utrecht in triumph ; and Quatremer Disjonval, who 

 had watched the habits of his spiders with so much 

 intelligence and success, was as a reward for his in- 

 genuity, released from prison. 



Another creature coiled up under the stone, 



