452 



NATURE 



{March 22, 1877 



the caterpillars which live permanently in the dark, or those 

 of the Microlepidoptera, just as little as those of the first stages 

 of development of most butterflies, have no markings at all ; 

 their small size, or their habit of hiding themselves, sufficiently 

 protect them from their enemies ; they, therefore, need no 

 markings to insure their safety. When the caterpillars are 

 getting bigger the longitudinal streaks become useful, as through 

 them they do not contrast so much with long-shaped leaves, fir- 

 needles, or stems. The caterpillars with longitudinal streaks, 

 such as those of Satyrida, Pieridcc, &c., almost without excep- 

 tion live on fir-trees, grass, or plants growing among grass. 

 The oblique streaks in the segments of other green caterpillars 

 imitate the lateral ribs of the large leaves upon which these 

 species live. The eye- and ring-shaped spots form another 

 means of protection. On the one hand, they may imitate the 

 berries of the plants on which the caterpillars feed, and protect 

 the latter, inasmuch as the berries are still unfit to be eaten at 

 that particular time {Deilephila hippophaes). On the other hand, 

 the spots, greatly resembling eyes, most decidedly act as means of 

 frightening the enemies of the larvae ; this is particularly the 

 case with the Chcerocampa species, as, whenever any danger 

 threatens them they draw their foremost segments into the fourth 

 and fifth ones, and the eye-spots upon these then glare on the 

 puffed-up fore-part of the animal. Weismann has proved this 

 experimentally, by throwing such caterpillars as food before 

 birds, and then watching the expression of fear on the part of 

 the latter. There are other caterpillars the markings upon which 

 cannot possibly be looked upon as means of frightening their 

 enemies, as their repulsive odour or taste alone suffice to ward* 

 off the insectivora. Wallace has shown that such insects bear 

 their many coloured marking like a stamp of their unfitness for 

 food, and already by this frighten off insectivorous animals 

 Weismann has proved by some experiments that lizards not only 

 refuse certain caterpillars (S?nerintkus, Sphinx, &c. ) at all times, 

 but are even diffident towards others which are marked in a 

 similar manner although quite edible, and only eat them after 

 minute examination. 



It is certain that many of these useful markings were acquired 

 by natural adaptation (Naturzuechtung), and it is quite beyond 

 doubt that others have resulted from the internal laws guiding 

 the formation or growth of caterpillars, i g., through correlation 

 of the different parts of the insect, independently of all useful- 

 ness. This is proved by the retrograde movement of the mark- 

 ings acquired in later stages towards the earlier ones, where the 

 markings can but be perfectly useless. The eye-spots,^ in the 

 same way, first appear through natural adaptation near the head 

 or the tail of the animal, and are then of use ; but later on they 

 spread oyer the other segments also, and here they only reappear, 

 because in articulata the general tendency exists to develop all 

 segments in an equal manner. On the other hand the gradual 

 disappearance of certain markings must be ascribed to natural 

 adaptation, because under different conditions of life, more useful 

 markings supplanted the existing ones, which had become useless. 

 If the second phylogenetic form of the Sphingidce caterpillars 

 with single longitudinal streak, seems to indicate that the animals 

 then lived on grass, the?e streaks became useless and even 

 obnoxious when the caterpillars selected shrubs and trees for 

 their food, and were then replaced by the more appropriate and 

 useful eye-spots. 



In short, as far as Weismann investigated the markings of 

 caterpillar?, particularly those oi Sphingidce, he could prove their 

 development to be caused by external influences (natural adap- 

 tation and subsequent correlation), and could consequently 

 reject the assumption of a special creative or form-shaping 

 power. 



HALBERTIS'S EXPEDITION UP THE FLY 

 RIVER, NEW GUINEA 



'T^HE Sydney Mail of Saturday, January 20, contains 

 -*- a long account of the expedition of the Italian 

 naturalist, D'Albertis, up the Fly River, New Guinea, 

 translated from his diaries, and communicated by Dr. 

 George Bennett. Signer D'Albertis left Sydney, April 

 20, 1876, in the mail-steamer, Brisbane, and reached 

 Somerset, Cape York, on May i, where the steam- 

 launch Neva, which had been provided for the purpose of 

 the expedition by the liberality of the good citizens of 

 Sydney, was disembarked and equipped. On May 19, 



after various small casualties, a start from Port Somerset 

 was effected, and Katow, on the coast of New Guinea, 

 reached on the second day. Hence the mouth of the 

 Fly River, already well known to D'Albertis from his 

 previous expedition in the Ellangowan, in 1876, was 

 soon entered, and more or less progress was made every 

 day. The land traversed appears to have been mostly 

 low and swampy. On June 20, being on shore, Mr. 

 D'Albertis ascended a hill 250 feet high, and from the 

 summit saw some " very high mountains " in the north- 

 east, fifty or sixty miles distant — probably part of the 

 " great Charles Louis range." On June 28, after having 

 been for some time aground, and only got off by an 

 unusually heavy flood, it was determined to return and to 

 try the western branch of the Fly River. The strong 

 current and other adverse circumstances rendered it ne- 

 cessary to abandon this attempt likewise, after about a 

 week's struggle, and the Neva returned to the coast, when 

 the expedition passed several months amongst the islands, 

 and finally returned to Somerset in November. The fol- 

 lowing is Mr, D'Albertis's summary of his discoveries : — 



" After my long narrative I shall conclude with a few 

 words expressing my regret at not having been able to do 

 more. But it is often not the pioneer who shows the way 

 that attains the most glory, but those who follow him ; it 

 is easy to hear of a road, but very difficult to find one 

 out. I wish every success to any explorer of this part of 

 New Guinea (should I not be able to return and complete 

 my work), and I hope that the little I have done will be 

 some guide and enable him to find his way more readily 

 than I did mine, and to correct any errors I may have made. 

 By this exploration we are now acquainted with a road into 

 the interior of New Guinea, which is of the more import- 

 ance, as it is so near to Somerset, where a line of large 

 steamers calls twice every month. We have also found a 

 passage from Moatta to the Fly River, shorter and safer 

 than the one previously known, and a passage which, when 

 properly surveyed, may be found navigable for larger 

 ships. The richness of the land we visited, its vegetable, 

 and probably mineral, products, the soil suitable for many 

 of the most valuable plants, as coffee, sugar, cotton, india- 

 rubber, sago, tobacco, nutmeg, &c., ought to attract the 

 capital of the colony to open up the country. The Dutch 

 from their part of New Guinea, although on a small scale, 

 derive some trade. The part of New Guinea into which 

 we penetrated, was in latitude 5° 30' S., and ran about 

 500 miles on the winding river, the course of which may 

 be seen on the chart appended, and it almost forms a line 

 of demarcation between that part of New Guinea claimed 

 by the Dutch, and that remaining as yet unclaimed by 

 any nation. 



"About the Fly River, as far as I could judge, the natives 

 appear less numerous than I have seen in other parts of 

 New Guinea, and the land is cultivated in a smaller 

 quantity, so that in this part of New Guinea the settler 

 will not find the same difficulties which I have pointed 

 out on former occasions when speaking of the south- 

 eastern peninsula, where the natives are more nume- 

 rous, and possess and cultivate all the best land, 

 have appended Baron von Mueller's report on my coUel 

 tion of dried plants ;^ and on the return of Prof. Liversidg^ 

 to Sydney he will report on the small collection of minerals, 

 &c., I submitted to him for examination. On a day not 

 far distant I hope to give the ethnological report on the 

 natives, their weapons, &c., also on the mammals and 

 the birds collected, the latter consisting of about fifty 

 species, many of which are new, or only recently described 

 from specimens obtained during my first visit to the Fly 

 River. I have also a rich collection of i-epti!es, fishes, 

 both of salt and fresh water, some beetles, and some fresh 

 water and land shells. I confidently expect that the voyage 

 of the Neva will be remembered by those who take an 

 interest in New Guinea, and by the scientific world." 



' Some extracts from this were given in our last issue, p. 438. 



