LYCOPODIE.E. 



[ 408 ] 



LYMPHATIC GLANDS. 



II. PsilotecB. Sporanges compound, 

 many-celled. 



BiBL. Spring, Blonograph. des Lycopo- 

 diacees, Mem. Acad. Bruxell. xv. ; Miiller, 

 Entw. der Lycopodiaceen, Bot. Zeit. iv. 

 1846 {Ann. Nat. Hist. xix. p. 27, &c.) ; 

 Bischoff, Krypi. Gew. Niirnberg, 1828. p. 

 97; Hofmeister, Vergleich. Untersuch. 

 Leipsic, 1851. p. Ill, &c.; Metteuius, Beitr. 

 zur Botanih. Heidelb. 1850. See also 



LYCOPODIE^.— A family of Lycopo- 

 diaceoiis plants, distinguished by their sim- 

 ple one-celled sporanges. The existing kinds 

 are all herbs, mostly creeping over the 

 ground; but some of the fossil kinds, met 

 with especially in the Coal-measures, were 

 large trees. 



Genera. 



I. Lycopodium, Linn. Sporanges all 

 of one kind, containing numerous small 

 spores resembling pollen-grains. 



II. Selaginella, p. de Beauv. Spo- 

 ranges of two kinds, the greater part resem- 

 bling those of Lycopodium; one, situated 

 at the base of the spikes, larger, often 

 foiu'-lobed, and containing only four large 

 spores. 



LYCOPODIUM, Linn.— A genus of Ly- 

 copodiese : this has already been sufficiently 

 characterized under the head of Lycopodia- 

 ceae. There are more than half-a-dozen 

 British species, mostly alpine plants, but 

 L. inundatum occurs on bogs in all parts of 

 Britain. The species usually described as 

 L. Selaginoides has oosporanges and anthe- 

 ridial sporanges, and belongs to Selagi- 

 nella. 



BiBL. Hook. Brit. Flora; Babington, 

 Man. Brit. Botany ; Francis, British Ferns 

 and their Allies, 5th ed. See also under 

 Lycopodiace^. 



LYGODIUM, Swartz.— A genus of Schi- 

 zseous Ferns, consisting of beautiful climbing 

 plants, \^dth conjugate, palmate, lobed or 

 pinnate leaves, having the sessile sporanges 



Fig. 441. 



in double rows on the teeth of the pinnules 

 Fig. 442. Fig. 443. 



h^T^' 



Lygodium reticulatum. 

 Fig. 441. Portion of a leaf, with fertile pinnules. Nat. 



size. 



Lj'godium reticulatum. 



Fig. 442. Tooth of a pinnule with overlapping indusia. 



Magn. 20 diams. 

 Fig. 443. The same, with the indusia removed to show 



the sporanges. Magn, 20 diams. 



(fig. 441), each having a hood-like special 

 indusium (figs. 442, 443). 



LYMPHATIC or CONGLOBATE 

 GLANDS. — The structure and functions of 

 these organs are not agreed upon by physio- 

 logists. 



Each is surrounded by a capsule, consist- 

 ing of areolar tissue, with numerous scattered 

 fine elastic fibres (nuclear-fibres), and, in 

 animals, unstriated muscular fibres. 



The substance of the glands consists of a 

 cortical and a medullary portion. 



The cortical portion, which in the larger 

 glands forms a layer about 1-6 to 1-4" in 

 thickness, exhibits a coarsely granular ap- 

 pearance, visible externally through the cap- 

 sule. This granular appearance arises from 

 the presence of a large number of septa 

 prolonged from the capsule into the sub- 

 stance of the organ, and dividing it into 

 alveoli; they are about 1-96 to 1-36" in 

 diameter, and of a rounded or polygonal 

 form. They are more distinct in animals 

 than in man. The septa consist of areolar 

 tissue with a few fine elastic fibres, and nu- 

 merous delicate spindle-shaped bodies re- 

 sembling fibro-plastic corpuscles, often ana- 

 stomosing at their ends. 



The contents of the alveoli are greyish- 

 white, pulpy, traversed by capillary blood- 

 vessels, and by numerous delicate fibres and 

 plates, composed of spindle-shaped and 

 stellate cells, resembling those found in the 

 septa, but forming a lacunar or spongy- 

 tissue. The soft substance consists of free 

 nuclei and rounded cells, resembling those 

 found in the lymph and chyle. 



The medullary portion exhibits no septa. 



