REVIEA^S. 355 



reducing experiments, the results, owing to the lightness of the coal 

 particles, and the consequent ease with which they are floated off, 

 come out surprisingly near to the truth. In travelling, we may dis- 

 pense with the washing bottle, by employing, in its place, a piece of 

 straight tubing drawn out abruptly to a point. This is to be filled by 

 suction, and the water ' expelled with the necessary force by blowing 

 down the tube. A tube 6 inches long and the fourth of an inch in dia- 

 meter, will hold more than a sufficient quantity of water to be used 

 between the separate grindings.* The mortar should be but slightly 

 inclined, and the stream of water must not be too strong ; otherwise, 

 especially if the coal be ground up very fine, portions of the pyrites 

 may be lost. The proper manipulation, however, is easily acquired by 

 a little practice. 



A Monograph on the British Spongiadce. By J. S. Bowerbank, 

 LL.D., F.R.S., F.L.S., F.G.S., F.Z.S., F.R.A.S., &c., &c. Vol. 

 T., 1864. 



Among recent contributions to Zoological science, a high place must 

 be assigned to Dr. Bowerbank's researches respecting the Sponges. 

 On occasion of the completion of his papers laid before the Royal 

 Society we referred to the interest belonging to them, and gave a slight 

 notice of his mode of arrangement, (vide Canadian Journal, vol. VII., 

 p. 468). We would now direct the attention of our readers to the 

 portion already published of his valuable monograph on the British 

 Spongiadse issued by the Ray Society. If he had chiefly occupied 

 himself in this work with the characters and history of the genera and 

 species occurring on the British coasts we should not have thought it 

 likely to interest many in a country where the objects could rarely, if 

 ever, be seen, even as preserved specimens in a museum, and where 

 anything at all similar can rarely be found ; but as the volume now 

 before us is devoted to the anatomy and phygiology of the Spongiadse, 

 a subject both curious and novel, which cannot fail to prove attractive 

 to all lovers of nature, we have thought that any information we can 



* In the third edition of his Probirkunst, p. 60, Plattner alludes to the use of 

 a tube of this kind, as a make-shift for the washing bottle, in reducing opera- 

 tions ; but in the new edition, this reference to its use is omitted. 



