AMYLOID. 



[ 39 ] ANALYTIC CRYSTALS. 



tate ; about 1-50,000" in length (PI. 53. 

 fig. 5). They are formed within the latici- 

 ferous vessels, but also within cells or fibres, 

 and between the cells. They are coloured 

 yellow by iodine, sometimes purple by sul- 

 phuric acid. They seem to correspond to 

 amylaceous Bacteria. They sometimes ex- 

 hibit rapid movements. Their formation 

 within closed spaces has raised the question 

 of spontaneous generation. 



BIBL. Trecul, Compt. rend. 1865-7-8; 

 Nylander, Flora, xxxviii. 522, 1865 ; Robin, 

 -flftcr.881; v.Tieghem, Butt.S. bot. Fr.xxiv. 



AM'YLOID. This name was given by 

 Schleiden and Vogel to a peculiar modifica- 

 tion of vegetable substance met with in the 

 thickening layers of the cell-walls, in the 

 cotyledons of certain Leguminosae, viz. 

 Schotia speciosa, S. latifolia, Hymencea 

 Courbaril, Mucima wens, M. gigantea, and 

 the tamarind (Tamarindus indicd) ; also of 

 the common white Haricot bean. When 

 in a dry condition, it is of a soft horny con- 

 sistence ; when wetted, it softens, becomes 

 gelatinous and transparent ; it is soluble in 

 boiling water, strong acids, and in solution 

 of potash, but not in alcohol or ether. It is 

 coloured blue by iodine, like starch, the 

 compound being soluble in water with 

 change to a yellow colour. The ' amorphous 

 starch/ described by Schleiden, in the seeds 

 of Cardamomum minus, in the rhizomes of 

 Carex arenaria and Sarsaparilla, seems 

 scarcely distinct from amyloid ; it forms a 

 thick viscous layer lining the cells. Amyloid 

 forms a transitional substance between 

 starch and bassorin and cellulose, and pro- 

 bably presents modifications approaching 

 more nearly to one or other of them in dif- 

 ferent plants. 



"When cellulose .is treated with a mixture 

 of 4 parts of sulphuric acid and 1 of water, 

 it swells into a clear jelly, which is at first 

 stiff, but gradually acquires liquidity ; alco- 

 hol or water throws down from it white 

 flakes of amyloid, which are coloured blue 

 like starch by^ iodine. It differs, however, 

 from starch in the circumstance that the 

 iodine can be washed out of it, and the blue 

 colour made to disappear by the action of 

 water, which is not the case with starch. 



The so-called Amyloid substance of Vir- 

 chow consists of a nitrogenous matter, 

 closely allied to albumen. It is coloured 

 deep reddish-brown by iodine, the addition 

 of sulphuric acid sometimes producing a 

 bluish-black or violet tint. It occurs in tis- 

 sues and organs affected with the waxy or 



lardaceous degeneration, as the small arte- 

 ries, the liver, the kidneys, the spleen, and 

 the lymphatic glands. 



See CELLULOSE and STARCH. 



AM'YLCJM. See STARCH. 



AMYMO'NE, Glaus. A genus of Cope- 

 poda (Entomostraca). 



A. sphcerica and longimana. In dredg- 

 ings. 



BIBL. Brady, Copepoda {Ray Soc.}, ii. 28. 



ANABAI'NA, Bory. See TRICHORMUS. 



ANACALYP'TA, Kohl. A genus of 

 Mosses, made a section of POTTIA by Miiller. 



BIBL. Miiller, Syn. Muscor. i. p. 547; 

 Wilson, Bryol. Brit. p. 97. 



ANACH'ARIS, Rich. A genus of Hy- 

 drocharidaceae (aquatic Monocotyledon ous 

 Plants). A. Alsinastrum, Bab., which is 

 apparently identical with Udora canadensis, 

 a North- American plant, has become widely 

 diffused in Britain during the last few years 

 in ponds and streams. It is of great interest 

 to microscopic observers, on account of the 

 facility with which the . ROTATION of the 

 cell-contents may be observed in its living 

 tissues. It is commonly cultivated in jars 

 of water for this purpose. 



BIBL. Wenham, Qu. Mic. Jn. iii. p. 277. 



ANAL'GES, Nitzsch. Agenus of plumi- 

 colous Acarina, fam. Sarcoptidae. In the 

 species, the integument is striated ; the 3rd 

 pair of legs very large and long ; the abdo- 

 men entire. 



Five species ; on birds. 



BIBL. Megnin, Parasites, 1880, p. 149, 



ANACYS'TIS, Meneg. A genus of 

 Palrnellaceous Algae ; consisting of very 

 numerous spherical green cells, imbedded in 

 mucus, and enclosed in a lamellar envelope. 



A. marginata (PI. 52. fig. 8*). Found 

 floating in fr. wat. pools, or on other algae. 



A. Grevillei, on dead stalks of asparagus. 

 Other species. 



BIBL. Kiitz. Tab. Phycol.\. pi. 9. figs. 2-4; 

 % Alg. p. 209 j Berkeley, Gleanings $c. ; 

 H&ssa\\ Brit. Alg. ( C0cco<?/W0m);Rabenhorst. 

 Fl. Alg. ii. p. 52. 



ANALYTIC CRYSTALS. A term 

 proposed by Fox Talbot, in 1837, to desig- 

 nate those crystals which possess the pow r er 

 of analyzing polarized light, like the tour- 

 maline. The substances in which this pro- 

 perty is best exhibited are the nitrate of 

 potash, the sulphate of chrome and potash 

 dissolved in tartaric acid by heat, boracic 

 acid, the oxalate of chromium and potash, 

 allantoin, hippuric acid, urea, oxalate of urea, 



