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Koenenia mirabilis) rappresentante <li un nuovo online (Microtelyphonida) 

 >ws tin.- preliminary paper without figures 1>\ the same author: [ntorno ad 

 un ■ (Koenenia mirabilis) che crediamo rappresentante d'un nuovo ordine 



\-, however, the treatment bj Hansen and Sorensen seems to m< 

 id than that "i Grassi, and as the figures, in which I take- most interest, are very 

 . distinct, 1 shall chiefly abide bj this treatise written in English, with its plate, to the figure 

 : which I shall especiall) refer, as it shows the- animal viewed from the lower side The homology 

 ■ of Koenenia (o), which bj the authors have been uamed with the unfortunate ex- 

 mouth . while Grassi uses the much better one papilla boccale , with the probo 

 itonymphon is conspicuous, and the relation and situation as to the three foremost 

 pairs of linilis is exactly the same-. Through the proboscis of Koenenia a transition is next formed 

 the mouth-structure in the other Arachnida, where I. contrary to Hansen and Sorensen, and to 

 the prevalent opinion, find the same proboscis, and it has only to be pointed out that the probo 

 in the otha of Arachnida, on account of its position between the powerful gnathites, necessarily 



must become shorter and more strongly chitinous than in Koenenia; and nowhere, perhaps, is the 

 rtening and chitinizatiou so accomplished as in .the Telyphona 1 ) so nearly related to Koenenia. 

 But if the proboscis of Koenenia and thus of the other Arachnida is homologous with that of the 

 Pycnogonida, and if it has never been supposed or is impossible to consider the proboscis of Koenenia 

 as formed by a coalescing of oral parts or gnathites, then it must be said that there is no reason at 

 all to suppose such a coalescing in the proboscis of the Pycnogonida. 



In the figures 7 and 8 is next given a drawing of the proboscis of Koenenia, viewed from the 



and from below, but without any contribution as to its inner structure; it is only said that the 



muscles are very strong . and some fine, indistinct lines in fig. 7 may be taken as an indication of 



these muscles. It cannot, however, lie doubted that it is a sucking apparatus or a pump, as is also 



.vn even by a less strict examination. 



The genera Pallene and Pseudopallene show in their larval form, as well in the first as in the 



eat a difference when compared with the other larvae of Pycnogonida, that there 



might seem to I a enough to set them up as a particular type; but as the difference chiefly 



1 reduction of the embryonal legs or even a disappearing of these, it is morphologically 



•nail importance. I have not seen so young a stage as that I have drawn of Pycnogonum littorale 



pi. I. Eg. 1 and 2; the youngest stage I have seen, is that of Pseudop. spinipes, pi. I , fig. 7, where the 



embi iewed from the side, lying in the tgg, and with distinctly defined cheliforus, proboscis, 



and lir of ambulatory legs. In the cheliforus, the two outermost joints, the chela, are not 



ud every trace of embryonal le.y:s is wanting. That the swelling behind the cheliforus 



most pair of ambulatory legs, and cannot he one of the two pairs of embryonal 1 



iparison between tin- pn mouth <>f Koenenia and tin- composite mouth, 



Mil- gnathites, of thi irthropoda, and I think that the difference as t<> the mouth-struc- 



Lnnex that, while in the Axthro nerallj more pairs of limits , the gnatbit 



ped with t" their partaking in the catching of and preliminary 



: the Pycnogonida, all tl ponding limbs are kept away from the oral 



in the point r.f the papilla boccale . 



