6 ANGIOCARPOUS LICHENS. 



" The nucleus contained in the apothecium differs very 

 sHghtly from that of other Lichens. It is composed of 

 erect filaments pressed against each other, precisely as in 

 the proligerous lamina of a Lecidea, and united by the 

 intervention of a mucilaginous substance which greedily 

 absorbs water. These tubular filaments, open at their 

 free extremity, have exactly the form of the asci or utricules 

 of a Peziza. They are linear, obtuse at the summit, and 

 attenuated into a short pedicel at the base, which seems 

 to be the continuation of the filaments of the medullary 

 layer. In their young state they are perfectly transparent, 

 and contain an opaline humour, in which at a later period 

 appear hyaline globules, which are hence only visible on 

 moving the diaphragm of the microscope. Gradually 

 these filaments, which can be considered as no other than 

 the true thecae, assume a blueish tinge, which becomes 

 more intense with age, but which, nevertheless, is never 

 lost at any age, when the thecae are viewed by transmitted 



light. 



" The sporidia also become more and more apparent in 

 the theca3, being globose or oblong, and arranged in a 

 single series. On the final rupturing of the theca they 

 are set free, and become mingled Avith that mass of black 

 powder, from which, however, they are clearly distinct, 

 and whose origin it is very difficult to determine, because 

 it exists in the very earliest period of the formation of 

 the apothecium. The sporidium, either entirely spherical 

 or slightly longer than broad, is bounded by a hyaline 

 margin,* and colom'ed blue. These observations were 

 made on a specimen of Sphaerophoron coralloides collected 

 in the Vosges." 



To the above my own observations have added some 

 few additional particulars. The medullary layer is com- 

 posed of hyaline branched filaments, entangled into a 

 woolly web or mass, (see Plate I., fig. 1, a,) surrounded by 



* Montague is scarcely correct in terming this a margin, properly speak- 

 ing. It is, in fact, a hyaline sac, that appears like a margin under the 

 microscope. 



