TUBERACE^E. 



285 



377. Order Tuberaceae. In this order the sporocarp is 

 a rounded underground mass, composed of pseudo-paren- x 

 chyma and the asci with their contained 

 ascospores. In the Truffle (Tuber) the 

 sporocarp is large, and dark colored and 

 warty on the exterior. Internally it con- 

 tains narrow tortuous chambers, on whose 

 walls are the asci, containing two to eight 

 usually areolate or echinulate ascospores 

 (Fig. 192, A and B). The sexual organs, 

 as well as the early stages of the Truffles, 

 are unknown. 



378. The common blue mould, found 

 on all sorts of decaying bodies, and known 

 as Pemcillmm qlaucum (or P. crusta- 



^ " v C 



ceum), has recently been found by Brefeld 

 to be a member of this order. Its life-his- 

 tory is now pretty well known, and it in- 

 dicates what the early 

 stage of the Truffle 

 must in all probability 

 turn out to be. In 

 Penicillium the my- 



Fig. 192. Tuber me- 

 lanosporum. A, a por- 

 tion of a transverse sec- 

 tion, showing the asci, 

 with contained asco- 

 Celllim Sends Up a large spores; B, an ascus 



of 



number 



vertical 



with ripe ascospores. 

 Both mui-h magnified. 



hyphae, which branch After Tuiasne. 

 at the top, and produce chains of conidia 

 (Fig. 193). It appears, from Brefeld's 

 researches, that this stage is the only 

 one which the plant passes through 

 under ordinary circumstances ; by care- 

 ful culture, however, he succeeded in 

 making it pass into its sexual stage. 

 He found the sexual organs to be in all 

 essentials similar to those of Eurotium 

 (Fig. 191) ; like it, the carpogonium is a spirally twisted end 

 of a hypha, and the antheridium a branch growing out from 

 below it. The subsequent development is also much as in 

 Eurotium ; a thick covering forms over the fertilized carp- 



Fig. 193. PenMllium 



ain of' u ronidia: 

 Magnined.-Aftercooke. 



