236 B. H. Buxton, 



phatic org-au is a diverticulum from the diaphragm which becomes 

 filled with cells but remains open opposite the coxal glands. 



It is obvious that the blood supply to the saccule of the coxal 

 gland must be very limited; merely a branch of a sing-le artery, 

 and the lymphatic org-an of Kowalevsky appears to have been 

 evolved as a means o^ bringing- waste products directly from the 

 abdomen to the coxal glands. It is probably a recent addition to 

 the execretory system, as there is nothing analogous to it to be 

 found in any of the other arachnids, nor is it present in all scor- 

 pions. The organ itself (LO) forms a kind of sac with a thick 

 hyaline wall lying in the abdomen, its interior being occupied by 

 small lymphoid cells, among which are also found the larger phago- 

 cytic connective tissue cells, often containing granules; the nephro- 

 cytes of Beuntz.^) Anteriorly there is an orifice which opens 

 through the diaphragm into the capsule of the coxal gland, but it 

 has no direct connection with the saccule (photos 6, 6 a, 6 b, 6 c, 

 at LO). 



The walls of the lymphatic organ are certainly not muscular, 

 nor are any muscles attached to them, so there would not appear 

 to be any pumping action; the fluid either filtering in, or perhaps 

 excretory products being brought in by the large phagocytes of 

 the connective tissue, where they are worked over by the lympho- 

 cytes and passed on to the coxal gland. 



Just ventral to the lymphatic organ and running parallel with 

 it is a large blood sinus (VS) from which, no doubt, the lymphatic 

 organ is supplied with waste products (photo 6). 



Of the scorpions, I have examined representatives of four out 

 of the six recognized families. 



1. Fam. Buthidae. 



Subfam. ButJiinae. 



Butlms australis, Biskra. 



Buthus occitamis Banyuls, South France. All ages from the 



advanced egg; just born; one year old 

 up to adult. 



1) These cells help to eliminate carmine or other foreign substances 

 injected and therefore act as nephrocytes, but it can be shown by dif- 

 ferential staining that they also carry nutrient material from the intestinal 

 coeca, where it is stored up, to the various organs. 



