128 Dr. M. Laurie on the 



t»asis Pocock's classification *. I have enclosed in parentheses 

 the names of those genera which I have not had an oppor- 

 tunity of examining, and their position is in some cases 

 doubtful. So far as observation has gone the members of 

 the family Scorpionidse are all characterized by the katoi- 

 kogenic mode of development, the other families — luridte, 

 Bothriuridae, and Buthidaj — being apoikogenic. 



Fam. I. ScorpionidgB. 



Subfam. 1. ScoRPiONiNi. 



Scorpio^ {Ileterometrus), {Micephonus) , (CEcopetrus), Opisth- 

 ophthalmus, Palamnceus. 



In this subfamily the chelicera masticate the central cord 

 and there are dorso-lateral outgrowths from the free segments. 

 The lung-book lamellte have spiny free margins. Opisth- 

 opliifialraus might be erected into a separate subfamily on the 

 strength of the extraordinary outgrowths from the carapace 

 and prostomium. Scorpio^ however, shows an approach to 

 the prostomial outgrowth. 



Subfam. 2. Ischnurini. 



Ischnurus^ (Opisthacantkus), Optsthocentrus, (Clieloctonus), 

 (Chiromachus) . 



In this subfamily the cheliceraa send root-like processes 

 forward into the appendix, as described above. The lung- 

 books are spinous. This is Pocock's subfamily minus Ilor- 

 murus and lomackus, along with which some of the other 

 genera ought possibly to go. 



Subfam. 3. IIormusiki, nov. 

 Ilormurus, [lomachus) . 



The characteristic feature here is the absorption of nourish- 

 ment by the chelae, as described above. The lung- books are 

 spinous. lomachus seems, from Pocock's description, more 

 closely allied to Hormurus than to the Ischnurine series. 



Subfam. 4. Diplocentrini, Pocock. 



Dijalocentrus^ {Oi'clus), NebOj [Gyphocentrus) . 



Nothing is known in this subfamily of the later embryonic 



* Ann. & Mag. Nat. Hist. ser. 6, vol. xii. Kraepelin's arrangement 

 (Hanib. \^■i8s. Anet. 1890 and 1893), which is later, is almost identical as 

 the main gi-oups. 



