22S 



HARD W1CKE 'S SCIENCE- GOSSIP. 



appendages in the form of lengthened cilia originate 

 from various parts of the surface, in others the wall is 

 studded with warts, verrucoses or spines. The spore, 

 or sporidium, may be simple, when it is one-celled ; 

 compound or septate, when the interior is divided into 

 two or more compartments, owing to the growth of 

 septa from the cell wall ; the term pseiido-septate is 

 used when the cell contents break up into two or 

 more pieces, but true septa are absent ; it is not 

 unusual to find simple and pseudo-septate sporidia, 

 with various transitional stages in the same receptacle 

 — muriform, when the contents are broken into 

 pieces by divisions crossing at right angles. A r uelei, 

 or bright spots, usually precede the division of the 

 cell contents, although not unfrequently nuclei are 

 present in definite numbers in sporidia that never 

 undergo any further change. Commencing with white 



within a special receptacle. One or more of these 

 often consistently precede or accompany other forms 

 of fungi producing more highly developed reproduc- 

 tive germs ; thus spermatia are frequently mixed with 

 the group of microscopic fungi parasitic on living 

 leaves, and conidia frequently appear on the same 

 plant that eventually produces ascigerous fruit, as in 

 the candle-snuff fungus [Xylaria hypoxylon), the 

 white mealy-looking tips being due to their presence. 

 Oogonia are conceptacles containing locomotive 

 bodies called zoospores, the movements being due 

 to the presence of exceedingly slender cilia ; they 

 may be obtained from a white fungus common on 

 the leaves and seed vessels of the Shepherd's purse 

 ( Capsella bit rsa -past or is) . 



This association of diverse forms of fruit or bodies 

 presumably connected in some way with reproduction 



Fig. 134. 



Fig. 135- 



Fig. 136. 



there is a transition through pale yellow, buff, pink, 

 rich sienna or iron rust, dark brown, and violet, to 

 black, as seen in the mass, and recently an agaric 

 with green spores has been described. Other bodies 

 connected with reproduction, but whose exact func- 

 tions are imperfectly or entirely unknown, are 

 spermatia, minute sporules frequently enveloped in 

 mucilage and escaping in the form of a tendril from 

 conceptacles called spermogonia j the name was given 

 on account of their supposed male function, but the 

 question yet requires to be worked out. Stylospores, 

 also very minute, and generated on slender threads in 

 receptacles called pyenidia, or on a naked compacted 

 portion called a stroma. 



Conidia or Trichosporcs produced frequently in 

 bead-like or moniliform strings which break up at 

 the joints, from the tips of threads not contained 



Fig. 137- 



is expressed by the term Polymorph isvr, 

 Dualism, or Alternation of generations. 

 Leaving out of question certain ob- 

 scure unicellular organisms, whose asso- 

 ciation with the present group is not 

 definitely settled, every fungus consists 

 of two parts : a vegetative, whose 

 functions tend towards the well-being 

 of the individual, the most important 

 being that of nutrition ; and a repro- 

 ductive, specially concerned with the 

 production of spores, which, unde? 

 favourable conditions, directly or indirectly develop 

 into a plant similar to the one from which they 

 originated. The vegetative part consists of the 

 mycelium, or spawn, slender hyaline septate or 

 continuous threads that enter into the substance 

 upon which the plant is growing, for the double 

 purpose of absorbing food and fixing the individual. 

 In some of the lower forms, commonly called moulds, 

 these threads remain isolated, and at their upper free 

 tips are produced the spores ; but in the more highly 

 organised kinds, the threads are compacted into a 

 solid tissue, which generally constitutes the greater 

 part of the plant. Yet the structure is often fibrous 

 and readily divisible into threads, proving it to be 

 simply the result of a number of primitive threads 

 more or less grown together ; but in some groups the 

 vegetative part consists of spherical or polygona 



