570 W. BLAXLAND BENHAM. 



unable to state ; cei'tain it is that this is the form presented 

 by an amoebocyte examined under the ordinary conditions — 

 either fresh in its own fluid, or after the addition of salt 

 solution. But Rosa denies that such is the true form of the 

 corpuscle within the body — as Cattaneoand othei's have done 

 in the case of Arthropods and molluscs. According to him 

 this form, usually described and figured, is only assumed 

 under abnormal conditions. 



He describes the true amoebocyte of the common earth- 

 worms (Lumbricus and Allolobophora species) as consist- 

 ing of a small central body, surrounded by more or less 

 numerous " petaloid pseudopods," each of which consists of 

 a firmer margin and an extremely transparent central portion, 

 so that the pseudopods look like a number of loops (see Rosa, 

 fig. 41). , 



I have certainly observed similar amcebocytes in Octo- 

 chtetus (PI. 41, fig. 3); nevertheless, I have — even after 

 taking the pi'ecautions suggested by Rosa, of fixing the cells 

 with osmic acid or corrosive sublimate as the fluid issues 

 from the pores — observed corpuscles Avith a form represented 

 in fig. 2. 



Some of these amoebocytes contain yellow globules of 

 chlorogogeu ; though it does not seem necessary to distin- 

 guish these as an independent kind of cell. 



In Acanthodrilus annectens some of the amoebocytes 

 contained both these yellow globules or granules of chloro- 

 gogeu, and in addition some clear refringeut globules ; these 

 also liave short pseudopods, and few of them. 



In addition to these more or less spherical amoebocytes I 

 have noted in OctochaBtus — though as rarities in the dis- 

 charged fluid— some much elongated, spindle-shaped cells, 

 with clearer cytoplasm, containing finer grauules; the pseudo- 

 pods are few, at the ends of the cell (fig. 4). 



These long cells I found in considerable numbers by scrap- 

 ing gently the inner surface of the body-wall, along which 

 they appear to be creeping., These appear to coi-respond with 

 tlie "spindle-shaped cell" described by Ling Boom Keng in 



