ANCESTRAL SI'imcUS AND THKIlt lIAr.n.-. 



157 



The horizon from which this fossil was obtained is tin* Koeene Ter- 

 tiary, Garnet Bay, Isle of Wight. ' It is, therefore, probably somewhat older 

 than most European and American aranead fossils. 



According to Scudder, more than one-half the genera of known fossil 

 spiders to which species have been referred have been dcseriheil us new 

 and peculiar to Tertiary times. These genera include about two-fifths of 

 the species. Among the genera are some remarkable forms, such as Arcln ,i 

 and Mizalia, each of which is considered by Thorell and others as repre- 

 senting distinct families. 1 Further on I reproduce Merendt's drawings of 

 Archea paradoxa, to illustrate these peculiar forms. 



FIG. 385. FIG. 386. 



FIGS. 385 and 386. Views of Palpipes priscus, a fossil crustacean larva. (After Von Meyer.) 



Two genera only of the thirteen to which the American species are 

 referred are described as new, and to them are referred seven of the thirty- 

 two species. Other genera not before recognized in a fossil state, but here 

 recorded from American strata, are Titanoeca, Tetragnatha, and Nephila. 

 To enter into details, seventy-one genera of spiders have been described 

 from the Tertiaries, sixty-six from Europe, and thirteen by Scudder from 

 America, eight genera being common to both. Of these seventy-one gen- 

 era, thirty-seven are counted extinct, thirty-five from Europe, and two 

 from America, none of these extinct species being found in both countries. 

 The European genera are, as may be supposed, largely composed of amber 

 species, no less than fifty-two, including thirty-two distinct genera, being 

 confined to amber deposits, besides others which they possess in common 

 with the stratified beds. 2 



Palpipes priscus 3 has been so long regarded as a Jurassic spider that I 

 have alluded to it in this chapter, but that it is not a true spider, but 



1 Thorell, European Spiders, pages 223-233. 



2 Scudder, Tertiary Insects of N. A., page 51. I <l<> m.t li.-re include K<>at\ \<u-. 



3 Von Meyer, Palieontographica, Bd. X., pages 299-304, Taf. L., Figs. 1-4, Cassel, 1863. 



