APPENDIX. 203 



known as a " sponge crawl," which is simply a large 

 pen with slatted sides, placed in some swift tide-way. 

 They are kept here nntil thoroughly macerated, which 

 process occupies about a month. They are then stirred 

 about, and beaten until all the animal matter is re- 

 moved, when they are dried. Many of the sponges of 

 commerce are bleached with chloride of lime, Avhich, 

 although it improves their looks, is at the expense of 

 the durability of the tissues. 



Section II. Prcjmring Skeletons.— I do not now 

 recommend using chloride of lime. The bones should 

 remain under water, in some glass or wooden vesseh 

 until every particle of fleshy matter is dissolved. If 

 the bones are oily after they are bleached, they should 

 be once more immersed in water, and kept there until 

 clean. Skeletons of large Mammals often require 

 more than a year to macerate them properly. I now 

 remove all horny poi^tious, even of the feet and bill. 

 In articulating small bones, I now make use of a very 

 strong cement, which is advertised in my catalogue of 

 taxidermists' supplies. 



