4 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 81 



Sycandra (now Sycon) coacta (p. 55), Leucandra (now Leuconia) 

 heathi (p. 59), Leucandra (now Leuconia) apicalis (p. 67). These 

 were sent him from Monterey Bay by Prof. Harold Heath, of Stan- 

 ford University. 



Lendenfeld, in his large monograph on The Geodidae, described 

 in 1910 the following from California: Sidonops angulata (p. 24), 

 S. hicolor (p. 46), Geodia niesotHaena (p. 96), G. agassizii (p. 113), 

 G. mesotriaenella (p. 151), G. hreviana (p. 155), G. ovis (p. 161), 

 and Geodinella rohusta (p. 205).- Many of these, because of the un- 

 justifiably fine distinctions drawn, have proved to be identical and 

 must hence be regarded as synonyms. 



Finally, in 1926, I described three species: Gellius textapatina, 

 Esperella -fisheri, and Suherites gadus; and in 1927 three more: 

 Acarnus erithacus^ Plocatnia karykina^ and Plocamia (better Iso- 

 ciona) lithophoenix ; with a redescription of Desmacella (better 

 Ophlitaspongia) pennata Lambe, 1894. So far as I am able to as- 

 certain, this is a complete list of references to sponges from Cali- 

 fornia. Reference is made to the Bibliography, page 128, for com- 

 plete citations to the papers mentioned. 



PREPARATION OF ALCOHOLIC MATERIAL FOR STUDY 



Identification of sponges depends upon miscroscopic character- 

 istics, for it is utterly impossible to rely upon macroscopic features 

 alone. This need not unduly discourage attempts to identify species, 

 as it is possible to prepare a sponge for examination in about 10 

 minutes, especially if the material has already been hardened in 

 alcohol. 



Take a small portion (less than 1 cubic centimeter) that includes 

 some of the outer surface of the sponge, and place it on a clean slide. 

 With a sharp razor (a safety-razor blade will do), section the ma- 

 terial, if possible, both perpendicularly to the surface and tangen- 

 tially. In a surprisingly large number of cases, this will be found 

 to be possible; however, if only fragments can be obtained, they can 

 still serve. The sections or fragments should be less than 0.5 mm, but 

 may be nearly that thick to good advantage. Flood the material 

 with a few drops of absolute alcohol, dry with paper towel or blot- 

 ting paper, and repeat from one to three times as necessary to de- 

 hydrate. Add a few drops of carbol xylene and again blot dry to 

 complete the dehydration thoroughly. Add a few drops of xylene 

 to complete the clearing and, without drying more than slightly, add 

 some very stiff balsam and cover slip. A little stain, such as basic 

 fuchsin, may be added to the alcohol to advantage. Comparison of 

 slides thus made with illustrations as given herein should make 

 identification possible in most instances. 



