Maech 16, 1900.] 



SCIENCE. 



423 



are, is plain. A wide barrier of sea and arid 

 lands devoid of suitable vegetation separates 

 at the present time the regions in which these 

 insects, for the most part forest-loving, occur. 

 The sandy wastes of Arabia and the rocky 

 plateaus of Abyssinia are a great and impass- 

 able barrier, to say nothing of the Indian Ocean, 

 to the transfer of genera which frequent the 

 hot and dense forests of tropical West Africa 

 and the equally hot and heavily timbered low- 

 lands of India and the Malay archipelago. In 

 Arabia, the present dividing region, many of 

 these genera are altogether wanting. 



Pararge and I'hyllocharis, palaearctic genera, 

 may have entered the region in which they 

 now occur by migration along the Nile. It is 

 quite different with the genus Srenthis, which 

 occurs isolated upon the slopes of Kenia, Kili- 

 manjaro, and Ruwenzori, the lofty volcanic 

 peaks which dominate the plains of eastern 

 and southeastern Africa. The nearest locality 

 in which this genus finds representation at the 

 present time is in the Alps of Switzerland, the 

 Himalayas in India, and the Andean region of 

 Patagonia. That the genus Brenthis should 

 occur on the lofty summits of the East-African 

 mountains and be there as the result of a mi- 

 gration from Switzerland, the Himalayas, or 

 Patagonia, under conditions such as exist at 

 the present time, is an untenable hypothesis, 

 which no student would venture to advo- 

 cate. The occurrence of Hypanartia only in 

 Africa and South America, and the existence in 

 Africa of the genus Crenis, so closely related 

 to the South American genus Eunica, as scarcely 

 to be separable from it, are facts pointing 

 strongly to the existence in some remote time 

 of a land connection between the continents of 

 Africa and South America. Correlated with 

 the facts as to the distribution of these genera 

 of butterflies is the fact that in the avifauna of 

 Africa and South America we find the Struthi- 

 onidx, or ostriches represented in both localities, 

 and the species of the genus Ehipsalis, of the 

 Opuntiese occurring in the Cameroons and 

 Madagascar, are witnesses in the floral world 

 to the ancient bond between two now widelj' 

 separated continents. To these facts cited by 

 our author the writer may add the fact that in 

 the elder groups of the arthropoda, as for ex- 



ample the Phrynidse, similar instances of the 

 occurrence of closely related forms in Africa 

 and tropical America occur. These things all 

 go to confirm the view which is coming to be 

 generally held by geologists and paleontologists 

 upon apparently strong and sufficient grounds, 

 that in the mesozoic and elder tertiary, a union 

 between the Eastern and Western Hemispheres 

 existed by means of an Antarctic continent, 

 which has largely disappeared, but which at 

 that time, in some way united Africa and Mada- 

 gascar, and very probably likewise Australia, 

 to the land-mass now known as South America. 



Under the head of ' Mimicry ' the author 

 gives a list of forty-nine species which are 

 mimicked and sixty-six species which mimick 

 them. It is very doubtful whether this list is 

 correct in representing certain species as mimes, 

 especially where a species of Teriaa is repre- 

 sented as mimicking a Pieris, or a Catopsilia 

 the female of Teracolus. The cases cited, with 

 which the present writer is very familiar, do 

 not come under the head of ' protective mimicry ' 

 at all, but fall into the common category of 

 general resemblance or family likenesses. This 

 part of the work, while interesting, gives evi- 

 dence of less care in preparation and less famil- 

 iarity with essential facts than any other part 

 of the work. 



Upon the whole the student of African en- 

 tomology has great reason to be grateful to 

 Pi'ofessor Aurivillius for having had the patience 

 and zeal to prepare this monumental volume, 

 which must for years to come serve as a key 

 for unlocking the treasures of knowledge as to 

 the butterfly-fauna of the Dark Continent. 



W. J. Holland. 

 Western University of Pennsylvania, 

 February 24, 1900. 



Zoological Results based on Material from New 

 Britain, New Guinea, Loyalty Islands and 

 elsewhere, collected during the years 1895, 

 1896 and 1897, by Arthur Willey. Cam- 

 bridge, Eng., the U-niversity Press. 4to. 

 Part III., May, 1899; pp. 207-356; plates 

 XXIV.-XXXIII. 



Part III. of Dr. Willey's ' Zoological Results' 

 opens with an account by Gadow of the varia- 

 tions in the number and arrangement of the 



