PHRAGMICOMA. 



[ '^94 ] 



PHTHIRIUS. 



glasses a lens of 5" focus ; for the I5" a lens 

 of 8" focus. 



Microscopic photograplisare test ol^tained 

 with solar light ; but artificial light has been 

 used, as that from caniphene or gas for low 

 powers, the oxyhydrogen light for high 

 powers, andMaddox has used the magnesium 

 light. A gi-eat point is to secure clean pre- 

 parations, with the object sufficiently flat to 

 allow of being clearly ibcused all over ; this 

 sets a limit to the utility of the process ; 

 fm-ther, certain objects in which red and 

 yellow, or yellowish-brown colours exist, do 

 not transmit the hght, or only imperfectly. 

 It will probably be advantageous to bleach 

 many objects, as, for instance, insects and 

 their parts, by long maceration in turpen- 

 tine, sections of dark-coloTired wood by 

 nitric acid, &c., when they are intended to 

 be photographed. 



The purely photographic manipulation 

 cannot be given here, but requires the ordi- 

 nary skill in photography. Lengthened 

 particulars respecting the application of 

 photography to the microscope are contained 

 in the papers referred to below. 



BiBL. Ilighley, Qn. Mic. Jn. i. 178, 30o, 

 and ii. 158 ; Shadbolt, Q^(. Mic. Jn. ii. 1G5; 

 AVenham, Mic. Tr. 1855, 2. iii. 1 ; Rood, 

 Qu. Mic. Jn. 1802, 261 ; Hessling and Koll- 

 mann, Atlas, d. thier. Gewch. 18()2 ; Maddox, 

 Tr. Mic. Soc. 1863, 9 ; ibid. 1865, 34 ; Jn. 

 Lond. Photo. Soc. 1864 ; Mn. Mic. Jn. 1869, 

 27 ; Woodward, ihid. 29, vol. iii. 290; Qu. 

 Mic. Jn. 1870, 380; Brit. Jn. Photo. 1866; 

 Moitessier, Photog. Appliquee, 1860 ; Reich- 

 ardt and Sturenburg, I808, Mon.mik. Phot.; 

 Benecke, Photo(/r. 1869 ; Hermann, Phot. ; 

 Gayer, Micro-photor/r. ; M. M. Jn. xv. 258 ; 

 Frey, Das Mik. ; Beale, How Sfc, and the 

 notices therein. 



PHRAGMICOMA, Dumort.— A genus 

 of Jungermanniefe (Hepaticse), containing 

 one British species, P. Mackaii (Jung. 

 Mackaii, Hook.), occurring 

 rarely on trees and rocks, espe- 

 cially on limestone. 



BiBL. Hook. lir. Jung. 53 ; 

 Ekart, Sy?i. Junq. 59, pi. 9. 

 fig. 72 ; Endlicher, Gen. Plant. 

 Suppl. i. 472-9. 



I'HRAGMID'IUM, Lk. 

 (Arcgma, Fr.). — A genus of 

 Uredinei ( Coniomycetous 



Fungi), forming rusts very 

 common on Rosaceous plants. 

 They appear upon living 

 leaves, breaking through from 



Fig. 565. 



beneath the epidermis, and are chiefly dis- 

 tinguished from PuccixiA by the number 

 of septa which are contained in the spores 

 or pseudo.spores. P. bulhosum is common, 

 forming yellow and brown pulverulent 

 spots on bramble-leaves (see Aefj^ma). 



BiBL. Berk. (Aregma), Br. Fl ii. pt. 2. 

 358 ; Grev. Sc. Crypt. Flor. pi. 15 ; Tulasne, 

 Ann. Sc. Nat. 4 S(Sr. ii. 180, pi. 9; De Bary, 

 Brandpihe, 1853, 49, pi. 4 ; Fries, Sum. Teg. 

 507; Currev. Q. J. Micr. Sc. v. 117. 



PHR A(tM01'RIC'HA 'CE.E.— a family 

 of Coniomycetes, distinguished from Melan- 

 coniei by their moniliform chains of spores. 

 See CoxioMYCKTF.a. 



PHRAGMOT'RICHUM, Kze.— A genus 



Phragmidiuiii 

 bulbosum. 



Isolated basi- 

 diiim with four 

 septate sjioreH. 

 Mag. lOU diams. 



566. 



Fi?. 568. 



Fig. 567. 



Phragmotriehtim Chailletii. 



Fig. 566. Scale of a spruce-flr cone, with pustules. 



Half nat. size. 

 Fig. 567. A pustule, magnified 10 diameters. 

 Fig. 568. Vertical section across a pustule, showing 



the chains of sjiores. Magnified lUO diams. 



of Phragmotrichacepe (Stylosporous Fungi). 

 The plants form little tubercles bursting 

 out from beneath the epidermis, and con- 

 taining filaments arising from a sottish 

 fibrous stroma. The filaments (basidia) 

 are interrupted at intervals with cellular 

 spores (fig. 568), which ultimately separate. 

 P. Chailletii grows upon the scales of the 

 cones of Abies e.vcelsa. Other species grow 

 on the poplar and maple. 



BiBL. Fries, Si/st. Mi/c. iii. 4d'2 ; Sum, 

 Veq. 474 ; Berk. Crypt. Bot. 327. 



PIlTlIlR'irS, Leach.— A genus of 

 Anophira, family Pediculidae. 



Char. Legs of two kinds, anterior pair 

 formed for walking, pdsteiior pairs for 

 climbing ; thorax large, not distinctly sepa- 

 I'ated from the abdomen. 



