November i6, 1S93] 



NA TURE 



69 



•necessarily confined the respiratory organs to the abdominal re- 

 gion. Further, those on the anterior segments of the abdomen 

 would be gradually preferred for specialisation, as being nearer 

 to the cephalothoracic musculature, and to the shelter of the 

 limbs for the protection of the open stigmata. The Scorpionidre 

 alone, having highly developed musculature in the posterior 

 abdominal segments, have the respiratory invaginations nearly 

 evenly distributed along the middle of tiie abdominal region. 



On the diagram I have farther indicated a few suggested 

 homologies. I have elsewhere ^ brought forward evidence in 

 favour of the derivation of tracheae from setiparous glands. The 

 derivation of poison and spinning glands from similar structures 

 is generally admitted. The consequent homology between the 

 ■spinning glands and tracheae requires a slight modification. 

 When, as in the He.xapoda, most Myriapoda, and the Arachnida, 

 the tracheae are strictly segmental, and intimately associated 

 with limbs, they have probably arisen from the large bristle 

 sacs which secreted the specialised parapodial acicula ; spinning 

 glands, on the other hand, are more generally to be deduced 

 from groups of ordinary bristle sacs, although they may also be 

 deduced from acicular glands as well. It is important to bear 

 tliis qualification in mind, as it helps to throw light on a difticult 

 point in the morphology of the Araneids. While the two pairs 

 of spinning glands on the two pairs of mammillie are referable 

 to setiparous glands on rudimentary limbs, and probably homo- 

 logous with trachece, there are also, in the majority of spiders, 

 median spinning glands between the mammillae, which cannot 

 be brought into connection with any rudimentary limbs. This 

 difficulty is, however, fully explained by the position of the 

 abdominal cement glands in the Chernetid:^, which serve to 

 stick the eggs to the abdominal surface, in which position they 

 are carried about by the parent. In these animals we have, on 

 the second and third abdominal segments, median glands 

 (originally paired) occurring between the two pairs of tracheal 

 invaginations. In this case I should refer the trachece to 

 acicular glands, and the cement glands on the same segment to 

 groups of setiparous glands lying ventrally to the acicula. In 

 the genus Galeodes, rows of short powerful bristles actually 

 occur in the corresponding position, i.e. close to the median 

 line on the second and third abdominal segments, and form 

 the stigmatic combs, which are quite distinct from the stigmata 

 themselves. According to this derivation we might have two 

 pairs of spinning glands on each segment, one pair placed later- 

 ally on mammillys, and one pair close to the median line between 

 j the mammillae. This arrangement is actually found in tbe rare 

 I spider Liphistius, which has four pairs of spinning glands 

 I arranged as here described. This is especially interesting, be- 

 I cause in addition to other primitive features Liphistius is alone 

 I among known spiders in retaining at least nine distinct ab- 

 I dominal tergites.- 



I The facts and suggestions here briefly set forward are a small 

 j instalment of the results obtained during my researches on the 

 ' comparative morphology of the Galeodidae, which I hope shortly 

 to have ready for publication. I may, perhaps, add that the 

 net results of these investigations go far to establish that 

 classification which ranks the Arachnids as an independent 

 group of the tracheate Arthrpodos, as distinguished from that 

 which would deduce them from the specialised Crustacean 

 Limulus through the specialised Arachnid Scorpio. 



Huxley Research Laboratory. H. M. Bernard. 



THE PRESENT STANDPOINT OF 

 GEOGRAPHY. 



]YTR. CLEMENTS R. MARKHAM, C.B., F.R.S. 

 inaugurated the evening meetings of the new session of 

 Ihe Royal Geographical Society, on Monday night, by a presi- 

 dential address on the present standpoint of geography. He 

 gave a survey of the state of our actual knowledge of the earth's 

 surface, and pointed out the regions where exploration may 

 } still be done. Viewing exact delineation by trignometrical 

 1 •measurement as the crowning work of geography, he pointed 

 I out how incomplete the exact mapping of the land surface of the 

 j •globe still was, while the delineation of the bed of the ocean 

 ^ !had hardly been begun. In the Polar regions, of course, lay the 

 I 



1 Zool. Jahrh. vol. v. p. 511, and .-?««. and Mag. January, 1893. 



- £/. "Liphistius," R. 1. Pocock, Ann. and Mag. N. H. October, 1892. 



, NO. 1255, VOL. 49] 



greatest unknown areas, and the two expeditions now in the 

 field, Nansen's and Peary's, were referred to with some con- 

 fidence as to their probable success. Mr. Markham himself 

 believed that land exists between Prince Patrick Island and 

 Siberia, which ought to be discovered, and was inclined to 

 accept Lieut. Ilovgaard's theory of extensive land north of 

 Cape Chelyuskin. He indicated the delineation of the north coast 

 of Franz Josef Land as one of the more important pieces of 

 Arctic work for the near future. Consideration of the vast 

 Antarctic field was postponed until Dr. Murray's paper at the 

 next meeting. 



In Europe there remained scope for detailed survey in many 

 countries, and Mr. W. H. Cozens- Hardy's recent labours on 

 the frontiers of Montenegro are only a foretaste of what has to be 

 done in the Balkan Peninsula. The Cantabrian mountains on 

 the west, and the Caucasus on the east, contain still many 

 isolated unknown patches. 



In Africa the unknown had been diminishing within his 

 memory more rapidly than anywhere else, and the days of 

 suddenly-planned expeditions discovering features of the first 

 magnitude had altogether passed. What remain unknown are 

 two great areas in the Sahara, in the Tibesti, and Ahaggar 

 highlands, the negro kingdom of Wadai, and the region 

 stretching from Southern Abyssinia into the Somali Peninsula. 

 In countless places detailed work has to be done, such as Dr. 

 Gregory's study of Mount Kenia, and Mr. Scott-Elliot's similar 

 detailed survey of the Ruwenzori region, just undertaken. 

 The best future work for geography in Afiica lies in 

 surveying rather than exploring, and lines of survey 

 should be run across the continent in defined and well- 

 thought-out directions. 



Asia has also new ground to break into. The valleys 

 of Hadramant, in Arabia, are almost as little known as 

 the Antarctic regions, and Mr. and Mrs. Bent will shortly 

 endeavour to explore that district. In Asia Minor and 

 Persia much detailed surveying must be done. In Central 

 Asia there is Lhassa, unvisit^d by an Englishman for 

 generations, and a vast region in north-western Tibet, be- 

 tween 34° and 36° N., and 82" and 90^ E. is a blank upon our 

 maps, in spite of the magnificent journeys recently made by 

 Bower, Rockhill, and the Russian explorers. Nearer India, 

 Nepal is little known ; Kafiristan is absolutely secluded from 

 the European, and there could be no nobler ambition for 

 a young geographer than to be the first to explore Kafiristan. 

 The maze of mountain ranges and river valleys east of the 

 Himalayas has yet to be unravelled, and the whole interior of 

 Indo-China is full of opportunities for research. Korea, in the 

 far east, is yet far from being fully known. The great Malay 

 Archipelago must receive much more attention, and the 

 problems of western New Guinea alone, with the grand range 

 of the Charles Louis mountains, are well worthy of being 

 seriously attacked. Upraised coral atolls in the Solomon 

 Islands have been reported but not visited. As regards new 

 discovery, however, there is probably no undiscovered islet re- 

 maining in the whole Pacific. 



Australia, except some desert patches in the west, has been 

 practically explored, although immense areas have still to be 

 surveyed, and the development of colonial geographical societies 

 gives good promise of that continent being thoroughly studied 

 from within. 



In North America, Dr. George Dawson enumerates a number 

 of great stretches of land, aggregating several hundred thousand 

 square miles, absolutely untravtrsed by any intelligent white 

 man. These lie mainly north of the Arctic circle, between tht 

 great rivers that flow into the Arctic Sea and in Labrador, 

 Alaska also has its unknown tracts, and even in the Ur.ited 

 States there is much room for detailed surveys. 



Central America is not well known, and in South America 

 much of the Colombian Andes, the basins of the Japura and 

 Putumayo, the whole tract between the Andes and the Orinoco 

 and Rio Negro, are practically unknown. In Peru whole 

 provinces are unexplored, and many peaks unmeasured. 



Oceanography is only beginning to yield results, and other 

 departments of generalised physical geography are of growing 

 importance. The better instruction of intending travellers, 

 inaugurated by the Society, and carried out by Mr. Coles, has 

 done much to confer value on the observations of officials, 

 traders, and missionaries, while the more thorough study of 

 theoretical geography, now beginning, requires great extension 

 and elaboration before its work would be thorough. 



