76 Mr. J. Blackwall on new species of 
homogeneous membranes are formed by the excavation of the 
cytoblasts, I believe that he has not observed all the stages and 
transitions of the cytoblasts mto starch ; for he does not notice 
the formation of the starch from the excavated cytoblast. The 
formation of a homogeneous membrane (membrane-substance) 
from the external layers of the cytoblast appears to be a very pe- 
culiar process, which will hereafter explain how it is that this 
membrane is not formed round a perfect cytoblast, and the trans- 
ition of the latter into another state of aggregation (starch). 
Still we cannot explain the whole process: of the formation of 
starch throughout the organic kingdom from these imvestigations, 
which may be readily made in the manner stated. The above 
isolated instance is insufficient; [therefore refrain from any further 
comparison of the separate stages of the starch-formation. How- 
ever, this example, especially as it may be so readily observed, will 
constitute a sure starting-point from which we may trace the 
formation of starch generally. 
XI.—WNotice of Spiders captured by Professor Potter in Canada, 
with descriptions of such Species as appear to be new to science. 
By Joun Buackwatt, F.L.S. 
[Continued from p. 44.] 
Genus Tecenaria, Walck. 
19. Tegenaria civilis. 
Tegenaria civilis, Walck. Hist. Nat. des Insect. Apt. t. 2. p. 7; 
Koch, Die Arachn. (Fortsetzung des Hahn’schen Werkes), B.8. 
p. 37. t. 264. fig. 618, 619. 
Agelena civilis, Sundevall, Vet. Acad. Handl. 1831. p. 127. 
Araneus subflavus, Lister, De Aran. p. 59. tit. xvu. fig. 17. 
Family THErRip1ipZ. 
Genus THERIDION, Walck. 
20. Theridion quadripunctatum. 
Theridion quadripunctatum, Walck. Hist. Nat. des Insect. Apt. 
t. 2. p.290 ; Sundevall, Vet. Acad. Handl. 1831. p. 118; Hahn, 
Die Arachn. B. 1. p. 78. tab. 20. fig. 58. 
Eucharia bipunctata, Koch, Uebersicht des Arachnidensystems, 
Erstes Heft, p. 7. tab. 1. fig. 13. 
Araneus pullus, Lister, De Aran. p. 49. tit. xi. fig. 11. 
an eV in il ae, avn ; 
