PHACUS. 



[ 501 ] 



PHILODINA. 



PHACUS, Nitzsch, Duj.— A genus of In- 

 fusoria, of the familjr Thecamonadina, D. 

 (Crvptomonadina, E,). 



Char. Body flattened and leaf-like, usu- 

 ally green, with an anterior red (eye-) spot, 

 a single flagelliform filament, and covered 

 mth a resisting membranous integument, 

 prolonged posteriorly like a tail. 



Dujardin distinguishes this genus from 

 Euglena, E. by the constancy of the form of 

 the body, which vai'ies every moment in the 

 latter genus. 



P.pleuronectes (PL 24. fig. 62). Body 

 oval, almost circular, green, with slightly 

 marked longitudinal furrows, and a tail-like 

 prolongation one-third or one-fourth of its 

 length. Aquatic; length 1-630". 



P. longicauda (PI. 24. figs. 3 & 63) = 

 Euglena longicauda, E. 



P. tripteris. Aquatic. 



P. triqueira = Euglena triquetra, E. 



BiBL. Dujardin, Infus. p. 334. 



PH^ONEME.E, Kiitz.— Afamily found- 

 ed on obscure byssoid structures occurring in 

 foul water. 



PH J!:OSPOR.E. — A name applied by 

 Thuret to part of the Fucoideae. 



PHALLOIDEL— A family of Gastero- 

 mycetous Fungi, characterized by the pro- 

 trusion of a large clavate, columnar, stellate 

 body, or globular, hollow, latticed frame- 

 work, from the summit of the burst peri- 

 dium. The basidiospores must be observed 

 early here, as they fall off and form a deli- 

 quescent mass upon the hymenium when 

 the sporange is mature. The fleshy struc- 

 ture protruded from the dehiscent capsule is 

 composed of spherical cells very loosely 

 connected; the peridium, which is very 

 tough, is composed of closely packed, very 

 slender, filamentous cells. 



BiBL. Berkeley, On the Fructification of 

 Lycoperdon, Phallus, S^-c, Ann. Nat. Hist. 

 iv. 1 55, Brit. Flor. ii. pt. 2. p. 226 ; Ross- 

 mann, Bot. Zeit. xi. p. 185 (1853). 



PHASCACE^.— A family of inopercu- 

 late Acrocarpous (terminal-fruited) Mosses, 

 of minute dimensions, gregarious or csespi- 

 tose, with a simple or branched stem. Leaves 

 oblong, oval, lanceolate or spathulate, con- 

 cave, Avith a thick cylindi'ical nerve; the 

 cells of the leaves parenchymatous, looser at 

 the base, by degrees denser towards the 

 summit, mostly papillose. Capsules mostly 

 obliquely apiculate, with spores larger than 

 in most Mosses, but not so large as in Ar- 

 CHiDiUM. Columella soon vanishing in the 

 smaller species. 



British Genera. 



I. i\.CAULON. Plants very dwarf, grega- 

 rious. Capsule contained in the closed peri- 

 chsete. Calyptra mitre-shaped, deh.ate. 

 Inflorescence monoecious (authericUa on a 

 distinct branch at the base of the stem), or 

 dioecious (antheridia terminal on a distinct 

 plant), bud-like. 



II. Phascum. Plants csespitose. Peri- 

 chsete open. Capsule on a iongish stalk, 

 and mostly obliquely ajDiculate. Calyptra 

 dimidiate. Inflorescence monoecious (anthe- 

 ridia terminal in a bud on a distinct lateral 

 branch, or naked and axillary on the fruit - 

 bearing branch), or dioecious. 



PHASCUM, L. — A genus of Phascacea^ 

 (Acrocarpous Mosses), which is now sub- 

 divided variously by diff"erent authors. Wil- 

 son separates the earlier Ph. alternifolium 

 only, imder the name of Archidium ; foreign 

 authors fmther distinguish between Phas- 

 cum, AcAULON, Ephemerum, and Asto- 

 MUM. Species retained: P^.crisjjwm, Hedw.; 

 cuspidatuin, Schreb.; curvicoUum, Hedw. ; 

 rectum, Smith; bryoides, Dicks. Ph. cuspi- 

 datum is very common on banks, and espe- 

 cially on a gravelly soil. 



BiBL. y^ihon, Bryol. Brit. 32; Hooker, 

 Brit. Fl. ii. pt. 1. p. 6. 



PHI ALUS A, Bory, Ehr.— A genus of In- 

 fusoria, of the family Trachelina. 



Char. Body not cihated, having a kind of 

 neck crowned with cilia; mouth lateral, 

 without teeth. 



P. viridis (PI. 24. fig. 61). Body oval, 

 flask-shaped, green, suddenly narrowed in 

 front and gradually behind; neck short. 

 Aquatic; length 1-290". 



P. vermicularis. White ; aquatic. 



BiBL. Ehrenberg, Infus. p. 333. 



PHILODINA, Ehr.— A genus of Rota- 

 toria, of the family Philodinaea. 



Char. Eyes two, cervical; tail-like foot 

 with horn-like lateral processes. 



Ehrenberg describes seven species; they 

 are all aquatic, and in general structm-e and 

 appearance closely resemble Rotifer. 



P. erythrophthalma (PI. 35. fig. 17). Co- 

 lourless, smooth, eyes round, processes of 

 foot short. Aquatic ; length 1-120 to 

 1-50". 



P. roseola is reddish, and the eyes oval; 

 P. collaris has a projecting cervical ring; 

 P. citrina has the middle of the body yel- 

 lowish ; P. macrostyla has oblong eyes, and 

 the foot-processes very long ; in P. megalo- 

 trocha the eyes are oval, and the rotatory 

 organs very large; and in P. aculeata the 



