556 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxvm. 



(Guerin, 1817), jdnicuHiv (v. Beneden, 1870), and the following which were simply 

 named by Richiardi in 1880, yi.s-.s-Ms, Irpklopl, petersH, iter rani, mnariK, and fruchati; and 

 lessonianus (Risso, 1816). 



(layi is here included from a printed ligure, the description not having been seen. 

 And finally, the author has been unable to secure either the figures or descriptions of 

 Iteptaims (Otto, 1821) or hyalbmn (Czerniavski, 1868). 



1. Carapace distinctly more than half the entire length 2. 



1. Carapace about hal f the entire length 25. 



1. Carapace decidedly less than half the entire length 41. 



2. Abdomen four-jointed and shorter tlian genital segment; the latter (piadrate. 



aiUincus, new species, [>. 576. 



2. Abdomen two-jointed and longer than genital segment; all males 3. 



2. Abdomen two-jointed, the same length as genital segment 5. 



2. Abdomen two-jointed, shorter than genital segment 11. 



2. Al)domen one-jointed, longer than genital segment 12. 



2. Abdomen one-jointed, the same length as genital segment 13. 



2. Abdomen one-jointed, shorter than genital segment 17. 



3. Abdomen joints about ecjual Ixmilo, new species, p. 589. 



3. Abdomen joints unequal, the first much the shorter 4. 



4. Genital segment oblong, no wider than abdomen; fifth legs invisible dorsally. 



strotiKttei (Kroyer, 1863). 

 4. Genital segment quadrate, three-quarters wider than abdomen; fifth legs 



visible, large nijimaculatus, new species, p. 561. 



4. Genital segment Vnirrel-shaped, one-third wider than abdomen; fifth legs 



visible, small schistonyx, new species, p. 564. 



5. Males, fifth legs plainly visible dorsally 6. 



5. Males, fifth legs not visible dorsally 7. 



5. Females, fifth legs not visible dorsally 10. 



6. Genital segment quadrate, half as wide as carapace; fourth legs large, all their 

 spines serrate and a large plumose seta at the tip of the basal joint. 



coryphxnx (Steenstrup and Lutken, 1861). 

 6. Genital segment quadrate, half as wide as carapace; fourth legs weak, no serrate 



spines, no seta' thymni ( Dana, 1852) p. 603. 



6. Genital segment oblong, one-quarter as wide as carapace; alwlomen almost the 



same width, joints e(iual (Uapltanvs (Nordmann, 1832). 



7. Genital segment ol)long, no wider than abdomen 8. 



7. Genital segment obovate or spindle-shaped, from one and a half to twice wider 



than the abdomen 9. 



8. First abdomen joint one-third the second; fourth legs short, just reaching the 



abdomen Irritaus ( Heller, 1865 ) . 



8. Abdomen joints the same length; fourth legs reaching Ix^yond tips of anal laminte. 



loinjipes (B-Smith, 1898, c). 

 9. Free segment narrower than genital segment; frontal plates narrow, lunules 



small gurnanll ( Kroyer, 1863 ) . 



9. Free segment same width as genital segment; frontal plates prominent, lunules 



large rapax (Milne-Edwards, 1840), p. 568. 



9. Free segment wider than genital segment; third and fourth legs large and 



stout _ imi.tiihi/iti, new species, p. 573. 



10. Genital segment rectangular, wider than long; fourth legs very short; furca 



double fallax (Kroyer, 1863). 



10. Genital segment obcordate, deeply lobed; fourth legs reaching beyond tip of 



abdomen lonyipi'^ (B-Smith, 1898, c). 



11. Males, genital segment sub(|uadrate; fifth legs visible dorsally. 



teres, new species, p. 649. 



