MR. W. H. BURRELL ON MVCETOZOA. 
451 
After a time, varying in different species from weeks to months, 
a change takes place, the protoplasm concentrates at numerous 
centres and gives rise to Sporangia ; each little heap assumes an 
outer pellicle, in many cases a stalk is formed that lifts it well 
above the substratum, and the interior portion undergoes rapid 
subdivision to form the spores and capillitium. 
The Capillitium is a kind of skeleton composed of delicate 
threads thickened, in many cases, with spiral or transverse bands 
or with nodules of calcium carbonate ; it writhes and twists with 
every change of atmospheric humidity, and regulates the dispersal 
of the spores. It may form a more or less complete network 
supporting the sporangium wall, as in Arryriu, Stemoniti s, etc. ; 
it may bo altogether absent, as in Licea ; or it may be broken up 
into separate elaters, as in Trichia. It affords some of the most 
reliable generic and specific characters of the class. 
According to Kerner, between four and five hundred species 
have been distinguished ; of these about one hundred and thirty 
are indigenous, and, so far as I have been able to ascertain, fifty-one 
species and varieties have been found in Norfolk (thirty-nine 
have been found within a six-mile radius of Sheringham during 
the past two years). Of the nineteen species given below, not 
included in Dr. Plowright’s lists, three are of special interest. 
Diacluva mbsessilis (Peck) is a rare species which, prior to 1896, 
had only been found in America, and appears to have been repre- 
sented by a single type specimen in the New York Museum ; in 
that year, however, it was found in Flitwick Wood, Bedfordshire, 
by Mr. J. Saunders of Luton (‘Journal of Botany,’ June, 1897), 
and in the autumn of 1897 Messrs. J. and E. Saunders found it 
again at Holt, the second European record. I have had the good 
fortune to obtain the loan of Miss Lister’s coloured drawing of 
the Holt specimen ; being of local interest, Mr. Saunders has 
most kindly suggested that it should be published in connection 
with this paper. I believe it has not been previously figured in 
any English work. 
Physarum straminipes (Lister), found on straw in a sheep-fold 
on the Sheringham Hall estate, October, 1898, is a species recently 
established on specimens found near Luton (‘Journal of Botany,’ 
May, 1898). 
