186 I)r. M. Laurie on the 



two subfamilies and only three genera, is not altogether 

 satisfactory; nevertheless, it was an attempt in the right 

 direction, and one of his subfamilies agrees with the family of 

 the Buthidse. 



Having a considerable number of Scorpions in my posses- 

 sion, it seemed worth while to investigate further on the lines 

 laid down by Professor Lankester, and see whether more 

 definite and satisfactory results could be attained. The 

 number of species at my command has, however, proved too 

 small to base any final conclusions on, though some points of 

 interest have come out. 



While I have examined every point which seemed in the 

 smallest degree likely to yield any information, I only deal 

 with three in the present paper. This is due to the other 

 points, such as the entosternite, having given purely negative 

 results. Two of the points I discuss are those dealt with by 

 Eay Lankester, and, in addition, 1 have taken the female 

 re])roductive organs. My material having been collected origi- 

 nally with a view to embryological work, the number of males 

 was too small to give any results. 



For my material I am indebted to Professor E. L. Mark, 

 of Harvard University, Mr. S. F. Harmer, Cambridge, 

 Mr. Peringuey, of the Cape Town Museum, Professor Thom- 

 son, of Stellenbosch, and Mr. R. L Pocock, of the British 

 Museum. I gladly take this opportunity of tendering my 

 sincerest thanks to all these gentlemen. For the correct 

 identification of my specimens — a point of importance for 

 this work — I am further indebted to Mr. Pocock. 



In so far as any classificatory terms are used without 

 specifying in whose sense, they are taken from Mr. Pocock's 

 classification *. 



In conclusion, I may say that I would be very grateful for 

 further specimens to enable me to continue this research. 



I. The Nervous System. 



The nerve-cord in the meso- and metasomatic segments, 

 with which alone we have to do, consists of a pair of longi- 

 tudinal cords bearing ganglia at intervals. These ganglia 

 (PI. IX. fig. 1) are seven in number and give off nerves on 

 each side to the segments to which they belong. A median 

 nerve has been described by Dufour f and Lankester \ passing 



* Anu. & Mag. Nat. Hist. ser. G, vol. xii. p. 303. 



+ Dufouv, " Hist. Anat. et Pliysiologique de Scorpions," Mem. pr^s. 

 a I'Acad. d. Sci. vol. xiv. (1856). 



X Lankester, "Position of Ganglia &c. in Scorpions," Proc. Roy. Soc. 

 1882. 



