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Atlantic (not very far from the coast of Portugal) at a depth of 

 1925 m. ; the "Siboga", finally, at three different places in the 

 Malay Archipelago and at depths varying from 825 to 1265 m. But 

 this does not change the rule, which still can be accepted as general, 

 viz. that whereas several genera of Cirripedia, and those of the 

 deepsea in the first place, are spread over the whole surface of 

 the earth, the species of Cirripeds and especially the deepsea-species 

 have been found to possess a very local distribution only. 



To close this article a few words on the relation of the deepsea- 

 forms to the extinct Cirripeds of which fossil remains have been 

 preserved. The material collected with the "Siboga" in this regard 

 also fully confirmed the conclusions arrived at by the working up 

 of the material from the "Challenger 1 '. The species of the genus 

 Scalpellum, which in the deepsea are so largely represented, have 

 their representatives already in relatively old layers of the earth-crust, 

 in secondary as well as in tertiary formations. We can even say, 

 that a great majority of the species of the deepsea, with regard to 

 an important anatomical characteristic (shape and structure of the 

 so-called carina), show the greatest affinity to the oldest fossil forms 

 (all those found in secondary formations); for this genus, therefore, 

 w r e can safely admit that the deepsea-species, at least to a certain extent, 

 show an archaic character. Side by side with the fossil Scalpellum's, 

 in the same formations and even in the same rocks or stones, numerous 

 species of the genus PolUeipes were found. To this genus of which 

 Darwin alone enumerated 22 different fossil species belong the oldest 

 known fossil Cirripeds and under the living it is still represented 

 by half a dozen species. The "Challenger", however, did not succeed 

 in collecting one single species of this genus even from slightly deeper 

 water, which, when the author worked up the material of the 

 "Challenger", gave rise to the remark, that the possibility of future 

 investigations of the deepsea bringing to light species of the genus 

 PolUeipes, could not be denied. Well then, the "Siboga" investigating 

 the deepsea very carefully in one of the areas, where one of the 

 living species of PolUeipes (P. mitella) is very generally distributed, 

 did not obtain from deeper water one single specimen of a species 

 of this genus either. So the exactness of the opinion pronounced in 

 1883, that, as far as the genus PolUeipes is concerned, the littoral 

 or shallow water forms have preserved a more archaic character, 

 has been completely confirmed by the results obtained with the 

 "Siboga"-expedition. Of the genus Verruca a few species have also 

 been found in older formations: one of these ( V. stromia) is still 



8* 



