BOTRYDIUM. 



[ 96 J 



BOTRYOSPORIUM. 



garis, forming a somewhat gelatinous, black- 

 ish-green stratum on the ground, on trees, 

 or on mosses, in damp places. 



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

 increase by 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, until the little 

 fronds acquire the dimensions of a pin's head 

 (l-36"Kiitzing); the whole cellular struc- 

 ture is firmly coherent. These bodies require 

 further study of development. 



BIBL. Brebisson, Nouv. Genr. d'Alg. 

 (1839) p. 3. fig. 3 ; Meneghini, Monog. Nos- 

 toch. p. 98. pi. 13. fig. 2 ; Hassall, Br. Freshw. 

 Alga, 320. pi. 81. fig. 2; Kiitzing, Tab. 

 Phycolog. pi. 10. 



BOTRYDIUM, Wallr. (Hydrogastrum, 

 Desv.). A genus of Siphoneae (Confervoid 

 Algae), of which one species is found in this 

 country, growing upon damp, clayey ground, 

 the dried-up bottoms of ponds, &c. A single 

 plant, as developed from a spore or gonidium, 

 exhibits a remarkable character, having a 

 lower branched filamentous portion, growing 

 in the ground, and an erect spherical or ob- 

 ovate portion, or head, about the size of a 

 mustard-seed, or a little larger, of a bright 

 green colour, the whole structure consisting 

 merely of a single cell, 

 with one continuous 

 cavity running through 

 the entire plant. The 

 figure (fig. 77) repre- 

 sents such a specimen, 

 with a second budding 

 from it by vegetative 

 increase ; and in this 

 way the plants come to 

 form tufts or groups, 

 like little bunches of 

 grapes; hence the name. 

 The cell - membrane 

 acquires considerable 

 thickness, and at the 

 period when it is soft- 

 ening, and about to 

 dissolve, to allow of the escape of the gonidia, 

 it is seen clearly to be composed of numerous 

 lamellae, like that of Hydrodictyon. The 

 globular head is lined, in the full-grown spe- 

 cimens, with a layer of protoplasm (primor- 

 dial utricle), containing abundance of chloro- 

 phyll globules ; and at a certain period, this 

 becomes broken up into numerous free glo- 

 bular portions, the gonidia. The gonidia do 



Fig. 77. 



Botrydium granulatum. 

 Magnified 10 diameters. 



not appear to " swarm," but escape by the 

 gradual solution of the parent globular sac 

 in which they are all produced. 



BIBL. Greville, Alga Brit. 196. pi. 19; 

 Hassall, Brit. Freshw. Alga, 305. pi. 77. fig.5; 

 Kiitzing, Nova Acta, xix. pt. ii. pi. 69. figs. 

 1-10; Braun, Verjungung in der Natur. pp. 

 136. 206. 236. 292; ibid. Ray Society's 

 Translation (1853), pp. 128, &c. 



BOTRYOCOCCUS, Kiitzing. Described 

 as a floating genus of Palmelleae( Confervoid 

 Algae), forming lobed and irregular bodies 

 about 1-24" in diameter, enclosed in a com- 

 mon, large, hyaline, membranous sac, and 

 containing a number of fixed granules, 

 1-7000 to 1-5000" in diameter, of a bright 

 or dark green or a red colour. Found in 

 lakes in Switzerland. It seems most likely 

 to have been a resting form of some Eu- 

 glena. 



BIBL. Kiitzing, Species Algarum, p. 892. 



BOTRYOCYSTIS, Kiitzing. Described 

 as a genus of Palmelleae (Confervoid Algae), 

 found in stagnant fresh water, but apparently 

 forms related to Volvox. They are globular 

 hyaline vesicles containing green granular 

 cells. B. Morum is 1-1200 to 1-120" in dia- 

 meter, with sixteen internal cells ; B. Volvox 

 1-600 to 1-96" in diameter, with numerous 

 internal cells. Braun describes a form con- 

 taining eight internal cells, apparently refer- 

 rible to B. Morum, where each internal cell 

 bore two cilia, which projected externally. 

 We have met with a similar organism. See 



VOLVOCINE^E. 



BIBL. Kiitzing, Sp. Alg. p. 208; Tab. 

 Phyc. pi. 9 and 10 ; Braun, Verjungung, &c. 

 p. 170; ibid. Hay Translation, 1853, p. 159. 



BOTRYOSPO1UUM, Corda (Stacliyli- 

 dium, Fries.). A genus of 

 Mucedines (Hyphomyce- 

 tous Fungi) allied to Bo- 

 try 'tis, but distinguished by 

 the lateral position of the 

 sporiferous branches (fig. 

 78). British species : 



B. diffusum, Corda (Sta- 

 chylidium diffusum,, Fr., 

 Botrytis diffusa, Greville), 

 forms loose white tufts, a 

 quarter of an inch high, on 

 decaying herbaceous plants, 

 especially potatoes. 



BIBL. Corda in Sturm 



DeutScU. Fl. iii.; Prachtfi. 



Enrop Schimm p. 39; 



Greville, Sc. Crypt. if I. Magnified 200 diams 



t. 126. fig. 2. 



