r>7i» 



Two features of iuten'sl strike one in llie (lislril)iiliMn of llie insecls of 

 llie I'acifie slope, viz, the absence ol' forms cliaraeterislic of .I;i|iimi and 

 Cliina, and (lie presence of some European ty])es wliieli do not occur in lln- 

 Eastern (Atlantic) province. We know so litlle of the I'liaL-enid fauna <if 

 China and ,la|)an Ihat tuir illuslralions must l>e horrowcd from other iinn- 

 ilies and insects of other (U-ders. Anions the Phahenids there are Ih/drid- 

 mcna soi-dklata, Pelrophoia fldrala, two species of L'lthoMege, SeUdo.semu, 

 Clnoplios, etc., which do not occni' in the Atlantic province, and are allied to 

 species or belong .to genera which occur in ivirope, but do not inhaltit North 

 America east of the Rocky ]\Ioun1ains. In other fanfilies of Lepidoplcra, 

 Papilio zulkaon represents tln^ European P. machuon, while the genus 

 PdiiHissius does not occur in the Atlantic province. The European Boni- 

 bvciil genera EpicaUia and Cdllarclia do not occur in the Atlantic province. 

 The Neuropterons genus Rhaphidia does not occur in tiie Atlantic States, 

 while Boreus calijaniicus is more like the European P. Injcmalis than the 

 two Atlantic species. 



On the other hand, we tind in \\\v Pacific States no such development 

 of the geims Lit/iosia as in Eun)pe, no species of Zygoma, no true Psi/cJiidfe, 

 no such development of the genus Hepialus, and any species of Lasiocampa 

 are wanting in Calitbrnia. We miss again in the Pacific' States any species 

 of Tropcea, a genus linking the Atlantic or Northeastern American entomo- 

 logical tamia with that of Northeastern Asia. Calitbrnia has evidently not 

 borrowt'd her insect fauna from Northern China or Japan. 



The main features in the geographical distribution of land-animals are 

 appai-ently the same with those of plants. Prof Asa Gray has shown* that 

 "almost every characteristic form in the vegetation of the Atlantic States is 

 wanting in California, and the characteristic plants and trees of Calitbrnia 

 are wanting here" (/. e., in the Atlantic States). We may, on the whole, 

 perhaps say of the Calitbrnian Lepi.loptera at least as Dr. Gray remarks of 

 the plants, that they are "as ditlcrent from [those] of the Eastern Asiatic 

 region (Japan, China, and Mandchiiria) as they are from those of Atlantic 

 North America. J'heir near relatives, when they have any in otiier lands, 



are mostly southward, on the .Mexican plateau The sanu' may 



be said of the [in.sects] of the intervening great plains, except that north- 



• Address at Dubuque meeting of tlio AiiuMkaii Assoc. Adv. SL-iencf, An;;., IST;^. 



