DORYPIIORA. 



[ 270 ] 



DRAPARNALDIA. 



broadly elliptical, ends produced ; length 

 1-500 to 1-800". 



D. Boeckii, S. (Cocconema JB., K.). 

 Valves elongate-lanceolate, ends somewhat 

 obtuse; length 1-144". This species appears 

 to have a median and terminal nodules. 



BIBL. Kiitzing, Bacill 74, Sp. Alg. 50 ; 

 Smith, Diatom, i. 77; Rabenhorst, Fl. Alg. 

 i. 126 (Raphoneis\ 



DORYPH'ORA, Illiger. A genus of 

 Subpentamerous (Tetrainerous, Latr.) 

 Coleoptera, fam. Chrysomelidse. 



The very numerous species are found in 

 equinoctial America. The thorax or me- 

 sosternum is armed with a long point, pro- 

 jected forwards. 



I), decemlineata (fig. 178*) is the Colorado 



Fig. 178*. 



Doryphora decemlineata. a, natural size ; b, eggs; 

 e, larva. 



potato-beetle. It is of an orange-yellow 

 colour, each elytrum being marked with 5 

 longitudinal, dark rough-edged strife. The 

 eggs are yellow, and attached to the under 

 side of the leaves of the potato, to which 

 plant the hatched larvae have proved so ex- 

 tremely destructive in America, as to have 

 annihilated entire crops. The beetle has 

 been brought over to this country by ship, 

 but has fortunately not become diffused and 

 naturalized. 



An Order in Council prohibits the keep- 

 ing of these beetles alive, under a severe 

 penalty. 



DOTHID'EA, Fries. A genus of Sphse- 

 riacei (Ascomycetous Fungi), often growing 

 upon leaves. * Distinguished from ObfaerM 

 and the more closely allied genera by the 

 asci being contained in cavities in the 

 stroma, without any distinct perithecium. 

 Numerous species are described as British 

 by Berkeley, some of which are now placed 

 under other genera by himself and Fries : 

 thus D. Geranii, Robertiana, Ranunculi, Po- 

 tentillce and Akhemillce of the Brit. Flora, 



and D. Chcetomium, Kze., are species of 

 STIGMATEA in the Summa Veg. ; D. alnea 

 is removed to DISCOSIA, and D. pyrenophora 

 and sphceroides are placed under DOTHIORA, 

 Fries, a stylosporous form. The whole of 

 these plants require further study, since it is 

 probable that they are really connected 

 with the Sphaeronemei or Melanconiei ; for 

 Berkeley's observations go to show that 

 Asteroma Ulmi is a form of Dothidea Ulmi, 

 while Tulasne has found upon Dothidea 

 Ribesii spores or sperniatia like those of 

 Xylari(S;oih&TS in excavated cavities having 

 the character of the spores of Septoria, 

 while in ordinary cases the surface is cov- 

 ered with conceptacles filled with eight- 

 spored asci. 



BIBL. Berk. Br. Fl ii. pt. 2. 285; Ann. 

 N. H. vi. 364; Berk, and Br. Ann. N. H. 

 2 ser. ix. 385 ; Fries, Summa Veget. 386, 

 418 & 421 ; Corda, Ic. Fung. iv. 119; Tu- 

 lasne, Ann. So. Nat. 4 se*r. v. 118. 



DOTHIORA, Fries. See DOTHIDEA. 



DOXOCOC'CUS, Ehr. A genus of In- 

 fusoria, of the family Monadina. 



Char. No tail; no eye-spot; motion 

 that of an irregular kind of rolling-over. 



D. ruber (PI. 30. fig. 47 a, after Ehr.). 

 Body globose, brick-red, more or less 

 opaque ; breadth 1-1728"; freshwater. 



This organism is almost beyond doubt the 

 same as that represented in PL 30. fig. 24, 

 d&n&f(nobis), i. e. a form of Trachelomonas 

 volvocina (TRACHELOMONAS). This was 

 suspected by Ehrenberg. 



D. milvisadus, E. (PI. 30. fig. 47 b) } is 

 probably an early stage of the same. 



The other two species D. globulus, sub- 

 globose or ovate, hyaline, marine, breadth 

 1-864"; and D. in<pqualis, subglobose, un- 

 equal, hyaline, speckled with green ; fresh- 

 water; breadth 1-2400" are probably 

 Algae, or their spores. 



BIBL. Ehr. Infus.y. 28. 



DRAPARNA'L'DIA,Bory. A genus of 

 Chaetophoraceae (Confervoid Algae), espe- 

 cially distinguished (as limited here in ac- 

 cordance with Kiitzing) by the filaments 

 being composed of an axis of cells of much 

 greater diameter than that of the tufted cells 

 forming the branches (fig. 179). The spe- 

 cies placed here by Hassall and others, de- 

 void of this character, will be found under 

 STIGEOCLONIUM. The green contents of 

 the cells form a broad band in the middle 

 of the cell. These plants are propagated by 

 4- ciliated zoospores, formed from the con- 

 tents of the cells of the branches (fig. 180) ; 



