HALISARCA. 



[ 382 ] 



HAPLOMITRIUM. 



laxly cellular lines ; umbilicus punctate, 

 entire ; diara. 1-720". 



H. iindenarins (PI. 18. fig. 51). Rays 

 eleven or twelve. 



BiBL. Ehr. Ber. Berl. Akad. 1844, 198. 



HALISAR'CA, Duj. (Hymeniacidon, 

 Bowerbk.). — A genus of marine Sponges. 



Forms a tliin semitransparent gelatinous 

 amber crust on rocks and shells, with indi- 

 stinct oscula and pores. 



H. Dujardinii. The only species. 



BiBL. Johnston, Br. Sponges ; Gosse, 

 Mar. Zuol. i. ; Bowerbank, Br. Spony. ii. 

 224. 



HALIS'ERIS, Tozzetti. — A genus of 

 Dictyotacea3 (Fucoid Alg*), containing one 

 British species, with a brownish olive, 

 sometimes forked frond with a midrib, from 

 4" to 1' high, having a very powerful otteu- 

 sive smell when fresh. The fructification 

 is produced in sori, arranged in lines on 

 each side of the midrib, or scattered, con- 

 taining large spores. 



BiBL. Harvey, Mar. Akj. 36, pi. 6 B. 



HALOCYTRIS, Dana.— A marine Os- 

 tracode, with very tliin, subquadrate, saddle- 

 shaped valves, beaked in front at the upper 

 angle. The closely allied Conchfscia, Dana, 

 has longer and subrectangular valves. Both 

 are related to Cypridina, and have two 

 pairs of feet, weak upper antennae, distinct 

 mandibles, large frontal tentacle, and no 

 eyes. 



Living in the Atlantic and Mediterranean. 



BiBL. Dana, E.vpL Exped., Crust. 1.301 ; 

 Bradv, Linn. Tr. xxvi. 409. 



HALTE'RIA, Duj.— A genus of Infu- 

 soria, family Halterina. 



Char. Body almost spherical or top- 

 shaped, with an anterior circle of cilia, and 

 a peripheral row of longer slender setae, 

 which by sudden contraction produce a 

 leaping motion. Freshwater. 



H. yrandineUa=Trichi)dina yrandindln, 

 Ehr. (PI. oO. hgs. 11, 12) ; greatest breadth, 

 1-850". 



H. volvo.v ; like II. yrandinella, but with 

 a second peripheral row of shorter and 

 closer cilia. 3 other species. 



Stein points out the resemblance of this 

 animalcule to the swarm-germs of an ^4c«- 

 neta foimd upon Cyclops. 



BiBL. Dujardiu, Inf. 414; Stein, Inf.; 

 CI. ct Each. Inf 369;" Kent, Inf 631. 



HALTERl'NA, CI. & Each.— A family 

 of Peritrichous Infusoria. 



Ci'iur. Free, globose or flask-shaped, with 



an anterior circle of cilia, and sometimes a 

 peripheral row of longer setae, which by 

 their sudden contraction produce a leaping 

 motion. 



Gen. : Halteria, with both cilia and setje ; 

 Strombidium, -with, cilia only; Mesodinium, 

 with a proboscis and setae ; Acarella, with 

 cilia and a carapace ; Arachnidkini, with 

 stout teutacle-hke cilia; and Uidinium, 

 with an anterior and posterior circle of 

 cilia. 



HAL'TICA, 111.— A genus of Coleopte- 

 rous Insects ; fam. Galerucidae. 



H. nemorum, the " turnip-fly." Oblong- 

 ovate, black ; elytra greenish black, with a 

 broad uninterrupted sulphm--yeUow streak, 

 not reaching the apex. Movement jump- 

 ing. 



BiBL. Stephens, Brit. Coleopt. 291. 



HALYME'XIA, Ag.— A genus of Cry- 

 ptonemiaceae (Florideoiis Algaj), containing 

 one British species, found on the southern 

 shores. It is a somewhat palmate, mem- 

 branous, rose-coloured sea-Aveed, usually 

 from to 12" long, composed of a double 

 membrane, the layers being separated by a 

 loose network of jointed filaments. The 

 fructification consists of faveUidia buried in 

 the frond, attached to the inner surface of 

 the membranous laminae, scattered all over 

 the frond, appearing to the naked e}'e like 

 red dots. 



BiBL. Harvev, Brit. Aly. 148, pi. 19 D. 



HAPAEOSI'PHON, Nag.— A genus of 

 Oscillatoriaceae. Filaments branched, formed 

 of a t-ingle row of cells, \A\h. delicate co- 

 loured, indistinctly lamellar sheaths. 



Four species; on freshwater plants. 

 (Rabenhorst, Fl. Alg. 283.) 



HAPLA'RIA, Link. See Botrytis 

 grisea. 



HAPLOMIT'RIUM, Nees.— A genus of 

 Jungermannieae (leafy Hepaticae), contain- 

 ing one British species, H. (Jiingermannia) 

 Hookeri, an Alpine plant, which lias been 

 carefully studied by Gottsche. It is re- 

 markable for having leaves (without amphi- 

 gastria) inserted on all sides of the stem. 

 The terminal capsule emerges at length 

 from a large oblong fleshy epigone (fig. 328). 

 The antheridia (fig. .323) occur in the axils 

 of. the leaves; they. have a double coat, the 

 interior of whicli consists of reniform cells 

 (fig. 322), which become isolated and more 

 or less dissolved. The spermatozoids, pro- 

 duced in minute vesicles (fig. 324), resemble 

 those of the Mosses. 



