38 Mr. F. P. Cambridge on 



4. E. ScHiJTT. " Centrifagale und simultaue Membran- 



verdickungcn." Jalirb. f. wiss. Bot. xxxv. 3, 1900. 



Gninardia baltica (figs. 11, \2)= G.jliccida (Cfistr.). 



Leptocylindrus daniciis (fig. S^) = RJnzosoIenia delicatula, 

 CI. (K. «v. Vet.-xViuid. llaudl. vol. xxxii. n. 8, 1900). 



Rhizosolenia setigera (fig. 34) = 2?. semispinal Hcnsen. 



Rhizosolenia Hensenii = 7i. setigera, Btw. P. T. C. 



5. Schroder. " Das Phytoplankton des Golfes von Neapel." 



Mitth. aus der zool. Stat, zu Neapel, vol. xiv. 



Asteromphahis Ralfsianus (fig. 7) seems to be a small form 

 of .1. Uvukeri^ but the fig. is not suffieicnt. It cannot repre- 

 sent ^4. Ralfsianus = A. hejAactiSj the central space being much 

 too large. 



Euodia arcuata, sp. n. (fig. S) = IJemidiscus cuneiformis. 



P. T. C. 



IV. — On the Genus Latrodectus, Walck. 

 By Fredekick Pickakd Cambridge, B.A., F.Z.S. 



In February 1902 a paper on this genus was read before the 

 Zoological Society of London, and a table giving differential 

 characters for the various species and subspecies was added. 



While executing the plates for that paper it has become 

 clear that certain characters, based on the clothing of the 

 abdomen, are of greater importance than I had considered at 

 the time to be the case, and I therefore publish the following 

 table as affording a better key to the characters of the different 

 species than that included in my paper read before the Zoolo- 

 gical Society. These characters will all be found illustrated 

 on the plates accompanying my paper in the ' Proceedings of 

 the Zoological Society.' 



Females. 



A. Integament of abdomen, at any rate on tlie 



lateral area, clothed with minute acanthoid 



spines, with or without longer bristles or 



spines. 



i. Abdomen clothed on the lateral area with 



