178 (db, a. C. OFDEMA.ITS) NOTES ON ACABT. 



Schrank says «nearly globular», but this mistake must be attrib- 

 uted to his imperfect microscopes. The fifth article is small too , 

 but lengthened and provided with a claw. The imperfect magnif- 

 ying glass in Schrank's time is cause that he did not interprete 

 this article as it really was. Schrank's fifth article is nothing else 

 but one enormously developed claw (see fig. 1 , 2 and 4). The 



legs are provided here and there with some smaller hairs, but 



« 

 the body is smooth , except that there are two hairs on the snout, 



looking like antennae. 



It is found in Coiifervaceae ; it dies when it is kept out of the 

 water; it does not come to the surface, nor does it vagabund, 

 but it crawls amongst the threadformed Algae. Schrank picked 

 it up in the last half of March. I however found it in March , 

 April, May und June, and I think it will be found during the whole 

 year when Confervaceae and Lenmaoeae are abundant in our ditches. 

 To this description I have to add tiie following: 

 Its length varies from 0.471 to 0.529 millimeters, its breadth 

 from 0.297 to 0.355 millimeters, the females being in average 

 longer and broader than the males. 



The colour is with the naked eye nearly black , with the mi- 

 croscope brown, with a yellowish spot on the fore part of the 

 metasoma (abdomen). 



The metasoma (abdomen) is oval and polished, but it shows 9 

 pairs of dermal pori, each provided with a small and smooth hair 

 (fig. 2 and 5). The prosoma (céphalothorax) is pentagonal, having 

 its broadest side anchylosed to the metasoma (abdomen). The 

 furrow which separates this last from the prosoma is indistinct in 

 the median line, just before the yellow spot of the metasoma. At 

 the top of the pentagon the two hairs «like antennae» (Schr.\nk) 

 are distinctly seen. On the end of the metasoma there are two 

 hairs too; moreover the prosoma shows two oval figures, formed 

 by a wall-like outgrow of the chitinous skin, prolonged by an 

 other nearly straight wall-like outgrow, the lamella (Michael), di- 

 rected forward and inward. At the end of this last there is a 

 pore. This spectacles-shaped figure is overlooked by Schrank. 



