BOERERA. 



[ 11^ ] 



BOTRYDmA. 



solution will sometimes yield tlieni, at otliers 

 not. Drops of the solution should be placed 

 upon a number of slides, and these laid 

 upon a warm iron plate. The disks are much 

 more beautiful than those ofoxalurate of 

 ammonia, appearing more transparent and 

 the colours more brilliant, probably from 

 their being more highly refractiye. They 

 are difficult also to preserve. Even when 

 mounted in Canada balsam, they deliquesce 

 after a time, and large crystals take their 

 place. 



BiBL. Fox Talbot, Phil Tr. 1837; 

 Brewster, Optics, 185.3. 



BORRE'RA, Ach.,=PHYSciA. 



BOS'MINA, Baird.— A genus of Ento- 

 mostraca, of the order Oladocera, and family 

 Daphniadae. 



Char. Head terminated in front by a 

 sharp beak directed forwards, and from the 

 end of which project the long, many-jninted, 

 curved and cjdindrical superior antennje ; 

 inferior antennoe two-branched, one branch 

 with three, the other with four joints ; fire • 

 pairs of les's. 



B. longlrosiris (Bl. 20. fig. 2). Superior 

 antennae with twenty joints. Fr. water. 



BiBL. Baird, Brit. Entom. p. 105 ; Ley- 

 dig, Daphnid. p. 244 ; Norman and Brady, 

 Br. Entom. (No/ih. and Eur ham Trans. 

 I p. 5). 



BOSTRYCHTA, Fries. See Cytispoea. 



BOSTRYOH'IA, Montague.— A genus 

 of Rhodomelaceae (Florideous Algae). 



B. scorpioides. Frond purple, slender, 

 branches involute at the end. Marine. 



I^IBL. Harvey, Mar. Alqcp, 79. 



BO'TACHUfe, Brady.— A genus of Cope- 

 podous Entomostraca. 



B. cylindratus. 



BiBL. Brady, Copepoda, i. 140. 



BOTIIREN'CHYMA.— Pitted tissue of 

 Plants. See Tissue, Vegetable, and refer- 

 ences under that head. 



BOTIIRIOCEPHALUS, Rudolphi.— A 

 genus of Entozoa, of the order Sterelmintha, 

 and family Cestoidea. 



Char. Body long, flat, soft and jointed, 

 joints short ; head slightly tumid, oval or 

 somewhat quadrangular, with two opposite 

 depressions, or with four ear-like appen- 

 dages, or with four depressions furnished 

 witli hooks ; genital pores mesial. 



The species are common in fish and 

 birds, more rare in mammalia, and very 

 rare in reptiles. They usually inhabit the 

 alimentary canal, sometimes the abdominal 

 cavity. 



Thirty-four species are enimierated by 

 Rudolphi, ten of which are doubtful. Du- 

 jardin enumerates twenty-three species. 



Bothriocephalus Jatiis {Tcenia lata, the 

 broad tape -worm) is met with in the human 

 intestines. The head is somewhat ovoid, 

 with two elongated opposite depressions, 

 but no hooks ; the neck generally not dis- 

 tinct. The joints of the body are very 

 broad in proportion to their length. The 

 orifices leading to the ovaries are situated 

 in the centre of the flat surface of each 

 joint; and around them the oviducts are 

 seen, having a radiated or stellate appear- 

 ance. Sometimes a minute body can be 

 seen projecting from the genital pore — the 

 male organ. It exclusively inhabits the 

 small intestines. It is rare in England. 

 It is 20 feet or more in length. Ova 

 1-350" long. Embryos ciliated, with six 

 hooks. 



B. cordatvs, with the head cordate, is 

 •found in dogs, and rarely in man (Leuckart, 

 ci: p. 438, fig.). 



' B. cristatus. With two prominences 

 forming a papillate rostrum. Human; 

 rare. 



See T^iEXiA and Entozoa. 



BiBL. Rudolphi, Entoz. Synops. ; Breniser, 

 Wiirmer, &c. ; Bujardiu, Helminth. ; Esch- 

 richt, Die Bothr. ; Blanchard, Ann. d. Sc. 

 Nat. 3 ser. xi. ; Davaine, Traite 8,-c. ; 

 Leuckart, Farasit. i. p. 416 ; Cobbold, Pa- 

 rasites, p. 106. • 



BOTRYCH'IUM, Swartz.— A genus of 

 Ophioglossaceous Ferns. Moon-wort {Bo- 

 trychinm Lunaria) is an indigenous repre- 

 sentative. 



BiBL. Hooker, Si/n. Fil., p. 447. 



BOTRYDl'NA, Breb.— A genus of Pal- 

 melleae (Confervcid Algae). B. vuk/aris, 

 the only species (PL 7. fig. 9), forms a 

 somewhat gelatinous, blackish-green stra- 

 tum on the ground, on trees, or on mosses, 

 in damp places. 



The spores, about 1-10,000" in diameter, 

 increase b}^ cell-division till they form sphe- 

 rical bodies composed of many cells, the pe- 

 ripheral layer of which is diaphanous, the 

 internal green from granular contents; the 

 internal vesicles multiply, with constant in- 

 crease of size of the whole, imtil the little 

 fronds acquire the dimensions of a pin's 

 head (1-36", Kiitzing) ; the whole cellular 

 structure is firmly coherent. 



BiBL. Brebisson, Noiiv. Gonr. cTAIg. 

 (18;59), p. 3, fig. 3 ; Meneghini, Monoy. Kos- 

 toch. p. 98, pi. 13. fi^. 2 ; Hassall, Freshu; 



