BIHANG TILL K. SV. VET.-AKAD. HANDL. BAND. 5. N:0O 18. 15 
pair of feet is two-jointed, the sete of the fifth pair 
of feet shorter and less developed, and the first abdo- 
minal segment equal to the others, being neither shorter 
nor longer. 
All these young forms described here resemble one 
another in the outline of the body as well as in the 
mouth organs, which are alike. Of course they present 
no sexual differences, but are destitute of the characters 
belonging to the male, and in general resemble the female 
most. I think it very possible that during these different 
stages the skin may be moulted several times without any 
external transformation. This would explain the singular 
fact that the individuals of the first cyclops-stage are much 
rarer than the mnauplius and the later cyclops-stages. It is 
also possible that the first cyclops-stage moults as many 
times as the other stages, but that it is passed through in a 
much shorter time. 
Measurement. 
Male: length of body with tail-set&e: 3,75 mm. 
> >» >» Without tail-sete: 2,2 mm. 
Female: length of body with tail-sete: 3,60—3.75 mm. 
D > » without tail-sete: 2,25—2,5 mm. 
Eqggs: diameter: 0,11—0,125 mm. 
Nawplius: first stage: length 0,15 mm., breadth 0,27 mm. 
second stage: length 0,20—0,25 mm., breadth 0,30—0,35 mm. 
Cyclops: first stage: length with tail-sete: 0,85 mm. 
> > > without tail-sete: 0,66 mm. 
second stage: length with tail-set&e: 1,3 mm. 
> > >» without tail-sete: 0,83 —0,85 mm. 
third stage: length with tail-set2: 1,90—1,95 mm. 
> > > without tail-sete: 1,15—1,25 mm. 
fourth stage: length with tail-sete: 2,4 mm. 
> 2 >» without tail-sete: 1,5 mm. 
fifth stage: length with tail-sete: 2,85—3,1 mm. 
> > > without tail-sete: 1.85—2,15 mm 
