1876,] REV. O. P. CAMBRIDGE ON EGYPTIAN SPIDERS. 567 



found in old buildings and under large stones at Alexandria and 

 Cairo. A strong specific character, not before recorded, so far as I 

 am aware, of the adult male, is furnished by a single longitudinal 

 closely set row of short but distinct and rather strong black spines, 

 reaching from near the base on the underside of the femora nearly 

 to the anterior extremity of the tibise of the first pair of legs. 



This Spider, described by Mr. Blackwall (Pholcus ruralis, I. c. 

 supru), is probably of this species. 



Fam. Theridiides. 

 Gen. Latrodectus, "Walck. 



LATRODECTUS EREBUS. 



Latrodectus e rebus, Sav. Egypte, pi. iii. fig. 9. 



Adult females, with their large globular brown egg-cocoons, were 

 found under stones among the ruins of an old building at Alex- 

 andria. 



Dr. Thorell (Europ. Spiders, p. 95) rejects the derivation of 

 Walckenaer's generic name Latrodectus from Xdrpov, wages or 

 reward, and heKTos, received, as yielding no rational meaning for 

 the name, and thence derives it from Xddpa, secretly, and Srjicrris, 

 biting. Those, however, who have looked most closely into the 

 derivations of names given to genera and species of animals know 

 best how very little rational meaning there is in a large number of 

 them, in cases where the derivation is almost, and sometimes abso- 

 lutely, certain. 



In a well-known instance a species of Lepidoptera was named by 

 a British author " decimella," merely because he had pinned it with 

 a number-few piu. Another instance is furnished by Baron 

 Walckenaer himself, who named a Spider " Carolinum " for (there is 

 no doubt) the excellent reason (?) that it had been found by his little 

 son Charles (Carolus). Rather than impute to the Baron the manifest 

 impropriety of writing Latrodectus, if he had really derived it from 

 XaOpa, I would suppose that he had some reason to look upon the 

 discovery of the type of his genus as the happy result of some 

 trouble or difficulty, and thus gave it the name (rightly written 

 Latrodectus) from the Greek words given as its derivation by 

 Agassiz (Nomencl. Zool.) and rejected by Dr. Thorell, i. e. Xurpos (a 

 form of Xd-pov), wages or reward, and Zebras, one meaning of which 

 is acceptable. If this be "no rational meaning for the word," it 

 appears to be, at any rate, more probable than the derivation given 

 by Dr. Thorell. The derivation given by M. Simon, Hist, des 

 Araignees, p. 1/7 (also rejected as irrational by Dr. T.), from 

 Xd-pevs, a workman, and ct]KT))s, a biter, would not be improbable, 

 since we find that Walckenaer (Araneides de France, p. 81, where 

 he confers the name) remarks especially on the manner in which 

 the Spider spins its snares for the entrapping of its prey beneath the 

 stones. 



