LUNULARIA. 



[ 480 ] 



LYCOPODIACEJE. 



a lung which has been injected from the 

 trachea with a very weak solution of nitrate 

 of silver; or in well-washed sections treated 

 with very dilute acetic acid; solution of 

 logwood is useful for staining. 



The lymphatics invest the subpleural 

 lobules in the form of a plexus, and dip 

 inwards to join the deep-seated tubes which 

 accompany the bronchi and large vessels to 

 the root of the lung. 



In the lower vertebrate animals, the 

 structure of the lungs is much simplar than 

 in the higher. Thus in the Trit&n each 

 forms a simple tubular sac, whilst in the 

 frog and toad (PI. 39. fig. 34) each lung 

 may be compared to a single lobule of a 

 lung of the Mammalia, having a cavity in 

 the centre, with which comparatively few 

 large cells extending into the periphery 

 communicate. The capillaries are also much 

 larger, especially in the two animals last 

 mentioned. 



BIBL. Kolliker, Mik. An. ii. ; Stannius, 

 Vergl. An. ; Waters, Human Lung, 1860 ; 

 Verson and Schulze, Strieker 9 ^ Hist. i. ; 

 Williams, Todds Cycl. An. j Luschka, Ar- 

 chiv mik. Anat. v. 1 ; Frey, Hist., and the 

 Bibl. 



LUNULA'RIA, Michel. A genus of 

 Marchantiese, growing on the ground in 

 shady places, having the perigones spread- 

 ing like rays from the top of the receptacle 

 (tigs. 319, p. 387, 329-331, p. 389), which is 

 a mere peduncle, so that an approach is made 

 to the character of the Jungermanniese. 

 See HEPATIC^:. 



LYCOG'ALA, Mich. A genus of Myxo- 

 mycetes, consisting of somewhat globular 

 bodies, verrucose on the outside, composed 



Fig. 422*. 



Lycogala epidendrum. Natural size. 



Filament and spores of the same. Magn. 200 diams. 



of a double papery peridium, containing 

 capillitium and spores, growing on rotten 



wood, &c. L. epidendrum (fig. 422*) varies 

 from the size of a pea to that of a nut, 

 is globular when solitary, deformed when 

 growing in groups, and of a red colour. L. 

 parietinum is bluish black, and the peridia 

 do not exceed 1-20" in diameter. 



BIBL. Berk. Br. Fl. ii. pt. 2. 307 j Ann. 

 N. H. 2 ser. v. 365; Grev. tfc. Crypt. Fl. 

 pi. 38 ; Fries, Syst. Mycol. iii. 79 ; Summ. 

 Veg. 448. 



LYCOPER'DON, Mich. A genus of 

 Trichogastres (Gasteromycetous Fungi) . The 

 species are commonly known as puff-balls, 

 from the cellular matter being absorbed, 

 leaving the spores free, mixed with a few 

 threads, and discharged like a puff of smoke. 

 The structure of the hymenium is noticed 

 under GASTEBOMYCETES j see also PI. 27. 

 fig. 6. The ignited mass of spores and 

 threads forms an anaesthetic. 



LYCOPODIA'CE^I. This order of 

 Cormophytous Flowerless Plants, which 

 derives its name from the Lycopodia or 

 Club-mosses, is difficult to characterize in 

 general terms. The bifurcating branched 

 stem, rooting at each fork by a slender 

 thread-like adventitious root, and the ordi- 

 narily small overlapping leaves, distinguish 

 most of the species of Lycopodium ; but 

 there is considerable variation from this 

 habit in the Psilotece, especially in Isoetes, 

 and the nature of the fructification is the 

 only mark generally applicable. The Ly- 

 copodiaceae bear spores which are found in 

 small dehiscent cases at the bases of the 



Fig. 423. 



Fig. 424. 



Lycopodium Gayanum. 



Fig/423. Scale of spike with axillary sporange ; side 



view. 



Fig. 424. The same seen from the outside. 

 Magnified 20 diameters. 



leaves (figs. 423, 426, & 427), on the upper 

 face or imbedded in it; and these fertile 



