312 ME. A. D. MICHAEL ON THE VARIATIONS IN THE 



described in the family, and some singular cases of the formation of spermatozoa and 

 spermatocysts not previously recorded. 



3. A description of a set of organs in the female genital system not previously 

 knoA^Ti, and which ajiparently serve chiefly for the maturation of the sperm-elements 

 within the body of the female, with the varieties of these organs in numerous species, 

 also some other not unimportant variations in the female reprodvictive organs from 

 any hitherto recorded in the family. 



4. A description of the female reproductive system, not before known, of a member 

 of the genus Sejus showing its similarity to those of the Uropodinae. 



5. A description of a pharyngeal skeleton and some other points of interest relative 

 to the alimentary canal. 



6. A few other novelties of less importance in the internal anatomy of the Gamasinae. 



Descriptions of New Species. 



II^MOGAMASUS HORRIDUS, Sp. n. (PI. XXXII. figS. 1-5.) 



Length without rostrum, about 



Breadth, about 



Length of legs, 1st and 4th pairs, without caruncle or ungues, about 

 ,j >■> 2nd „ 3ru „ „ „ „ „ 



Colour darkish umber-brown. 



Texture. Almost the whole dorsal surface is covered with a chitinous plate, Avhich, 

 however, is rather thin ; it is smooth but not polished ; there are not any markings 

 on the cliitin. The plate covers the fore part of the body but does not extend to 

 the posterior end ; a border of softer white cuticle is shown round the posterior and 

 the greater part of the lateral margins, especially in the female. 



Shape longish ; nearly parallel-sided, but somewhat wider behind than in front ; 

 posterior end rounded, anterior slightly shouldered and narrowed in. Dorsal surface 

 rather flat. 



Mandibles. Those of the male are exceedingly curious ; they are elaborate and 

 difficult to describe ; they will be best understood from fig. 3. The whole mandible 

 is short and thick for the family ; the fixed arm of the chela thick, not diminishing 

 in thickness until close to the distal end, when it suddenly curves downwards like 

 a parrot's beak ; but the projection of the beak below is very slight. There are 

 two minute teeth close to the beak ; the rest of the arm is rather undulated than 

 toothed. The movable arm of the chela is the more singular ; it is a broad undulated 

 piece without teeth until nearly opposite the end of the fixed arm, then there is a 

 break or indentation on the under edge ; from this point arises a great hook, which 

 first curves forward, then turns strongly backward, almost parallel to its outward 



