304 MR. E. I. POCOCK ON SCORPIONS 



Whether these specimens all come from one localitj or 150 

 localities, we are not informed. Probably some were from 

 Algeria, some from Egypt, and possibly some from Syria. But 

 we cannot learn from the treatise whether any variation in 

 structure was noticed between the Algerian and the Egyptian 

 forms. All the information that we get is the table of measure- 

 ments, which may have been taken from a dozen species, a brief 

 diagnosis, which also may apply to a dozen species, and the 

 loose statement that the species extends from Marocco to Arabia. 

 Now I venture to say, although with all respect to Prof. Kraepelin 

 as a most able and careful worker, that this is not the method of 

 monographing a genus that yields results of any permanent 

 value. Every systematist should remember thab naming a species 

 is only a means to an end — the end which should always be kept 

 in view being the discovery as to what is the relationship between 

 a species and its environment, and the primary work of the 

 systematist is to point out whether structural variation is corre- 

 lated with differences of distribution or not. In a large majority 

 of cases we know that there is such a correlation in terrestrial 

 animals ; and when in any case it has been definitely established, 

 the systematist may, to assist the recollection of the fact, assign 

 a name to the local form and call it a species, subspecies, or 

 variety, as he pleases. And if this has been done, it is clearly 

 the duty of a monographer carefully to examine the evidence for 

 and against the opinion of his predecessors, and not carelessly 

 and without comment to discard as synonyms the names that 

 they have proposed. 



Now this so-called species Prionurus funestus furnishes a good 

 instance of what has been said. "When Ehrenberg went to Egypt 

 he found that on the coast near Alexandria a particular form 

 was found : this he called libycus. But not being acquainted 

 with the differences between the young and the adult, be further 

 assigned a name to the young of libycus, calling it melanophysa. 

 Proceeding up the Nile, he found in Upper Egypt and in 

 Nubia another form which he at once recognized as different 

 ivova lihycus : to this he gave the na.me citrinus. Still further 

 to the south, in Dongola, he came across another form which he 

 looked upon as different from citrinus, and named funestus. 



Later on C. Koch obtained in Algeria a form which he saw 

 from Ehrenberg's figures was not known to occur in Egypt. To 

 this he gave the name hector ; but he also had another example, 



