119 



regular transverse lines ; though not so numerous they are 

 larger proportionately than in the preceding species. 



The head bears smaller and more rounded tubercles 

 than in the same species, the eyes are very small, the 

 ocelli (two or three) seem to be confluent. The face is 

 slightly excavated above, with the upper arcuate margin 

 not very distinct and slightly indented in the middle, 

 with the external angles definite, sculptured to accom- 

 modate the antennae, the cavities thus formed separated by a 

 median ridge. The first segment of the thorax is the longest; 

 its posterior angles are not deeply cleft, the cleft visible from 

 the outside ; the remainder of the lateral margin is a rather 

 thin edge. The following segments each become a little longer 

 from before backwards. The first abdominal segment is short, 

 the second has two transverse tubercles, the third, fourth, and 

 fifth are strongly tuberculate ; these segments do not project 

 much at their lateral extremities. The sixth segment is about 

 twice as wide as long, convex, curved under the body ; it bears 

 two transverse tubercles. Antennules are present, but are very 

 small. The antennse are short, the peduncular joints much 

 thickened in contrast to the small 2 -jointed flagella, the 

 proximal joints of which are very short. 



The mandibles are strong, the left one with three penicils, 

 the right one with two. The legs are moderately robust and 

 sparsely spined. The external rami of the uropods are want- 

 ing, the inner rami do not reach the end of the abdomen, the 

 peduncles are 5 -sided as seen from below. 



The colour is white, with pale-brown markings. 



The length is about 2 mm. 



DESCRIPTION OF PLATES. 



Plate II. 



Fig. 1. — Oniscus myrmecophilus, n. sp., 4 diameters. 



antenna. 



portion of left mandible, dis- 

 torted. 

 1st maxilla. 

 2nd maxilla, 

 maxilliped. 



last segment of abdomen, etc. 

 uropod from below. 

 1st pleopod, male. 

 2nd pleopod, male. 

 minuta, n. sp., 16 diameters. 

 ,, face with antenna. 

 ,, lateral margins of 1st two segments of 



thorax from below. 

 „ 1st leg. 



„ abdomen from behind. 

 ,, uropods from below. 



1. 



— Oniscus 



2. 



>> 



3. 



}) 



4. 



jj 



5. 



)) 



6. 



J 1 



7. 



5 J 



8. 



)) 



9. 



J> 



10. 



/-» " • 



11. 



— Cubans 



12. 



)> 



13. 



j> 



14. 



)» 



16. 



)> 



16. 



J • 



