234 i;nto.M(ji,o<;i,sk i idskrii-"]' 1901. 



between K. Wliceleri and the description (with figures) of K. 

 mirabilis published by Dr. Sörensen and myself. I will mention 

 all main i)oints as briefly as i)ossible. 



The author points out the existence of eight teeth on each 

 finger of the antennal chela (p. 621), but when she describes 

 the teeth tjn llie fixed finger as very different in shai)e from 

 those on the movable finger it is quite erroneous. It may be 

 sufficient to refer the reader to my description above and to fig. 

 2 c on pi. 2. — • On each side of the head she has discovered 

 »three sensory rods», which are shown in fig. 4 (p. 621); they 

 are figured as pillars of very different length and with their distal 

 end shortly conical (rather like stalactites, as a colleague remar- 

 ked), but this is very incorrect. I have found four organs on 

 each side, and each of them is shaped almost as the lateral 

 organ in A. mirabilis \ the organs are shown in fig. 2 b on pi. 2. 



The »lung sacs» discovered by Prof. Wheeler are mentio- 

 ned (p. 620); the apertures, which are seen when the sacs are 

 invaginated, have been observed, and in the chapter on the in- 

 ternal anatomy further information has been given. Here she 

 ^vrites (p. 626): »They are evidently evaginated through the 

 internal blood pressure. For each pair of sacs there is a pair 

 of dorso-ventral muscles, corresponding to the dorso-ventral muscles 

 of 'J'helyphonus, which have the function in Koenenia of drawing 

 in the everted sac appendages. » But in fig. 5 she lias drawn 

 four pairs of dorso-ventral muscles; without dissection I have 

 been able to discern five pairs in A'. Whcclcri (which has three 

 pairs of sacs) and I have also found these muscles in K. angusta, 

 a species without ventral sacs. The dorso-ventral muscles, which 

 exist in almost all and perhaps in all orders of Arachnids, have 

 in reality nothing to do with the sacs, but the contraction of 

 all the pairs in the abdomen may perhaps cause a blood pres- 

 sure which evaginates tlie sacs in K. ll'/iir 1er i and K. chilciisis. 

 Furthermore she writes that the sacs »possess on their inner 

 surface (inner when they are evaginated) granular bodies...»-, 

 above I ha\e written that I have been unable to discover any 

 contents within them. On my material some of the sacs are 

 evaginated as much as possible, and each contains a number of 

 »granular bodies» spread very irregularly on the inner surface; 



42 



