BULBOTRICHIA. 



[ 124 ] 



BURSARINA. 



These ultimately come to rest, and com- 

 monly attach themselves to germinate upon 

 the walls of the parent filament, often on 

 the outside of the mother cell of the spore. 

 When they germinate, they become short 

 filaments composed of one, two, or several 

 cells, in each of which is developed one or 

 two spermatozoids, which are minute glo- 

 bular active bodies with a wreath of cilia, 

 almost colourless, but in other respects re- 

 sembling the much larger zoospores. These 

 spermatozoids escape by the cells breaking 

 across, and have been observed to enter the 

 orifices in the walls of the parent-cells of 

 the spores and effect the fertilization. 



Prmgsheim has described a number of 

 species, characterized by the form of the 

 sporange and the unicellular or multicellu- 

 lar condition of the antheridial plants, and 

 by the relative dimensions of the organs. 

 We are not assured of the value of these cha- 

 racters, and confine our list to one species. 



B. setigera, Ag. (fig. 83), is a common 

 plant, and is variable in the relative length 

 and diameter of its cells, on which ground 

 Kiitzing has separated a B. minor, where 

 the diameter is equal to or greater than the 

 length. Hassall, Alg. pi. 54. figs. 1-4 j Dill- 

 wyn, Conferv. pi. 59. 



B. Pringsheimiana, Archer, Qu. Mic. Jn. 

 1866, p. 122. 



Rabenhorst describes 16 species. 



BIBL. Alex. Braun, Verjiing. (Hay Soc. 

 1853) ; Hassall, Ann. N. H. xi. 36 ; Alg. 

 209, pi. 64; Decaisne, Ann. d. Sc.Nat.2 se"r. 

 xvii. 335, pi. 14. fig. 5 ; Kiitzing, Sp. Alg. 

 429; Pringsheim, Berlin Ber. 1855 (Ann. N. 

 H. ser. 2. xv. 346; Qu. Mic. Jn. iv. 131, 

 1856) ; Jahrb. f. iviss. Bot. i. 11, 1857 ; De 

 Bary, Mm. Senckenberg, 1856, 29 ; Raben- 

 horst, Fl. Alg. iii. p. 357 ; Sachs, Bot. 281. 



BULBOTRICH'IA, K. A doubtful ge- 

 nus of AlgaB. 



Char. Filaments indistinctly jointed, 

 colourless, subcartilaginous, branched ; 

 branches bulbous at the base, tumid at the 

 apex, forming sporangia. 



B. botryoides. Forming a hoary-green 

 powdery stratum j sporangia green. On 

 roofs. 



B. peruana. On rocks. 



BIBL. Kiitzing, Tab. J%c.iv. p. 22; Ra- 

 benhorst, Fl. Alg. iii. p. 374. 



BULIMTNA, D'Orb. An important 

 group of Foraminifera, so called from their 

 Bulimine shape, due to an increasing and 

 spiral series of one, two, and even three 

 chambers, close-set, with their apertures 



towards the umbilical axis. The aperture 

 is an infolded notch of the septal face, and 

 usually oblique. The shell hyaline in the 

 young state, coarser in the adult. Many 

 fossil specimens are arenaceous ; these come 

 under Atavophragmium, Reuss. The va- 

 rieties are infinite, both recent and fossil, 

 and the names numerous. The oldest is 

 found in the Trias. B. Preslii, Reuss, is 

 typical. B. pupoides (PI. 23. fig. 46) is a 

 common Atlantic form. 



BIBL. D'Orb. For. Fos. Vien. 61 ; Wil- 

 liamson, Br. For. 61 ; Carpenter, Introd. 

 For. 194. 



BUNT. A disease of Cereal Grasses, 

 &c., depending on Fungi. See BLIGHT, 

 TILLETIA. 



BURSA'RIA, Ehr. A genus of Infuso- 

 ria, of the family Bursarina. 



Ehrenberg described fourteen species. 

 They are mostly found in stagnant fresh 

 water ; some in the intestines of the frog, 

 Nais, &c. 



B. vernalis (Panophrys, D., Frontonia, Cl. 

 & L.) (PI. 30. fig. 19). Body ovate-oblong, 

 turgid, green, rounded at each end, some- 

 what narrowed posteriorly, the mouth placed 

 behind the anterior third or fourth of the 

 body ; fresh wat. ; length 1-130 to 1-110". 



B. ranarum (Opdlina ran.) (PI. 31. fig. 

 47). Body ovate, lenticular, compressed, 

 large, white, the dorsal and ventral surfaces 

 keeled, anterior part subacute, often trun-. 

 cate posteriorly, mouth inferior, near the 

 anterior pointed end; length 1-210 to 1-70". 

 In the intestines of the frog. 



B. entozoon, Ehr., which is found in the 

 rectum of frogs, is Balantidium entoz. of Cl. 

 and Lachm. 



Cl. and Lachm. admit only 1 species : 



B. decora. Body urn-shaped, with a long 

 convolute nucleus, and very numerous con- 

 tractile vesicles, scattered through the par- 

 enchyma. Berlin. 



The species of B. (Ehr.) are referred to 

 other genera. 



BIBL. Ehrenb. Inf. ; Duj. In/us. ; Stein, 

 Infus. Entwickel. ; Clap, and Lachm. Inf. 

 p. 251 ; Kent, Inf. p. 574. 



BURSARI'NA, Duj. A family of In- 

 fusoria. 



Char. Body very contractile, of variable 

 form, usually oval, ovoid, or oblong, ciliated 

 all over ; a large mouth with cirri forming 

 a row or part of a spire. 



Claparede and Lachman divide the family 

 thus : 



