Mr. A. Scott on Scolecithrix hiberntca. 363 



reaching to near the end of the body, and composed of twenty- 

 four joints, the proportional lengths of which are shown in 

 the formula — 



I 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 

 12. lO.e.e. 5. 5. 6. 10. 6. 6. 7. 7. 7. 7. 7. 7. 7. 8. 8. 8. 6. 9. 10. 4 



The joints are only sparingly setiferous, but the twenty-first 

 and twenty-second have each one plumose seta on the distal 

 end of the lower margin ; the twenty-third bears two plumose 

 setae at the distal end — one on the lower and one on the upper 

 margin — while the twenty-fourth joint is furnished with two 

 plumose and two plain apical sette ; two short sensory fila- 

 ments — one a little longer than the other — spring from tlie 

 distal end of the upper margin of the second joint. Primary 

 branches of the antennse very short, two-jointed: secondary 

 branches fully three times the length of the primary ones 

 and composed of six joints, the third, fourth, and fifth joints 

 being veiy sliort ; both branches are furnished with a number 

 of plumose setse. Mandibles fairly well developed, the biting- 

 part armed with a number of small teeth; palp small, two- 

 branched, the upper branch very small and composed of 

 two joints, the lower considerably larger and apparently 

 four-jointed. Maxillae well developed and somewhat similar 

 to those of S. danue ; the foot-jaws also resemble those of that 

 species. The inner branches of the first pair of feet are one- 

 jointed, of the second two-jointed, of the tliird and fourth 

 three-jointed, while the outer branches of all the four pairs 

 are three-jointed. Tlie female has no fifth pair of feet. 

 Abdomen four-jointed ; genital segment as long as the com- 

 bined lengths of the second and third joints ; second, third, 

 and fourth joints of about equal length. Caudal stylets 

 slightly longer than the last abdominal segment, length 

 about equal to twice the breadth. 



Male. Somewhat similar to the female, except in the 

 following points : — The proportional lengths of the joints of 

 the antennules differ slightly, as shown by the formula — 



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 

 8. 8. 7. 4. 4. 4. 5. 8. 7. 6. 6. 7. 7. (5. 6. 6. 6. 7. 6. 8. (5.9. 9. 4' 



The mandibles are very small and somewhat rudimentary ; 

 the biting-part has apparently no teeth, but consists of an 

 evenly rounded edge ; the mandible-palp has the basal part 

 larger than that of the female ; the uppermost of the two 

 branches is small and two-jointed, but the lower one is large 

 and composed of three joints. The maxillge are also very 

 small and somewhat rudimentary. The anterior foot-iaws 



