A. E. HILTON ON CAPILLITIA OF MYCETOZOA. iJ' 



capillitium was thus gradually obscured. By 9 p.m. the colour 

 of the sporangia had deepened, indicating that spores were 

 forming ; and an hour later it had changed to a reddish brown. 

 Next morning, the sporangia were black; and by evening on 

 the following day were of a shining bronze-like appearance, 

 which they retained. 



From records of other observations,* it appears that the 

 elater-like threads of TricMa and Hemitrichia originate within 

 the plasm as vacuolar spaces which gradually become longer 

 and narrower until they traverse the sporangiimi in regular 

 rows. These lengthened vacuoles, containing substances in 

 solution, are at first nodular and uneven ; but as development 

 proceeds they become uniform, and a membrane is excreted by 

 the vacuolar fluids which forms the tubular wall of the capillitial 

 thread. On the outside of these membranous tubes further 

 material is deposited in the form of spiral bands, giving them 

 their twisted, rope-like appearance. The regularity of these 

 spirals is probably the result of physical forces comparable 

 to those of crystallisation but working in a coarser medium. 

 Contractions in drying render the spiral bands more prominent, 

 and wrinkle the underlying membrane so as to produce slender 

 ridges appearing as very fine lines running lengthwise along the 

 tube. When the sporangium wall is ruptured, the threads, which 

 are hygroscopic, twist and intertwine into a fibrous tangle. 



An interesting description of another of the TrichiaceaE;, 

 Cornuvia Serpula, has been given by our fellow-member, Mr. 

 J. M. Coon,f who found specimens of this minute species among 

 spent tan in Cornwall. The capillitium consists of branching 

 threads beaded at intervals with prominent ring-shaped thicken- 

 ings. A stained preparation of plasm in which the threads 

 were beginning to appear shows them to be tubular formations 



♦ By R. A. Harper and B. O. Dodge. See pp. 388 and 389 of 

 Journ. E. Micros. Soc, August 1914, for abstract of paper published 

 in Ann. of Botany, xxviii. (1914), pp. 1 to 18, 2 plates. 



■\ Journ. R. Micros. Soc, 1907, pp. 142-145, plates x. and xi. 



