508 METHODS FOR INVERTEBRATES. 



mate of potash. The stain is at first green, but becomes blue in tap 

 water or alcohol containing ammonia. 



MAYER simply uses a solution of pyrogallol in alcohol or glycerin ; 

 and HOFMANN (Zeit. wiss. Zool., Ixxxix, 1908, p. 684) puts for a day or 

 more into raw pyroligneous acid. 



Dr. ORTON writes to me that he simply uses picro-nigrosin and borax 

 carmine. 



948. Tracheae may be studied by the Golgi bichromate and silver 

 process. MARTIN (C. R. Soc. Philomath., 1893, p. 3) injects them 

 with indigo white (through the body cavity), and puts into hot water 

 from which the air has been expelled by boiling. Tracheae blue. 



949. Brain of Bees. KENYON (Journ. Comp. Neurol, vi, 1896, 

 p. 137 ; Journ. Roy. Mic. Soc., 1897, p. 80) treats by the GOLGI 

 process (seldom successful), or hardens in a mixture of 1 part formol 

 and 2 of 5 per cent, sulphate of copper, followed by staining in 

 Mallory's phospho-molybdic hsematoxylin. 



JONESCU (Jena. Zeit., xlv, 1909, p. Ill) has employed the silver 

 methods of Kamon y Cajal and Bielschowsky and Wolff. 



950. Ventral Cord. FLOYD (Mark. Anniv. vol., 1904, p. 355) fixes 

 the ganglia of Periplaneta for eighty minutes with vapour of formol, 

 and brings into alcohol. 



See also BINET, Journ. Anat, Phys., xxx, 1894, p. 469. 



951. Eyes of Arthropods. For the methods of LANKESTER and 

 BOURNE (Quart. Journ. Mic. Sci., 1883, p. 180 : Limulus) ; HICKSON 

 (ibid., 1885, p. 243 : Musca) ; PARKER (Bull Mus. Harvard Coll, 

 xx, 1890, p. 1 ; Zeit. wiss. Mik., viii, 1891, p. 82 : Homarus) see 

 early editions. 



PARKER (Mitth. Zool. Stat. Neapel, xii, 1895, p. 1) also applies 

 the methylen blue method to the retina and optic ganglia in Deca- 

 pods, especially in Astacus. He injects 0-1 c.c. of a 0-2 per cent, 

 solution into the ventral sinus. After twelve to fifteen hours the 

 animals are killed, the ganglia quickly dissected out, and the stain 

 fixed as described, 343. 



For his method for eyes of Scorpions see 575. 



For the methods of PURCELL for the eyes of Phalangida see Zeit. 

 wiss. Zool., Iviii, 1894, p. 1. He has the following stain. The 

 cephalothorax is removed and brought for twenty minutes into 

 50 per cent, alcohol warmed to 45 or 50 C., and saturated with 

 picric acid. The pigment dissolves in this solution and stains the 

 nuclei and some other parts of the rhabdoms, so that no further 

 stain is required. 



