284 



NATURE 



\_7uly II, 1878 



tarsus at all, nor any bones which we can with certainty 

 call "metatarsal." We have only one single long bone, 

 at the lower end of which are three or four cirticular sur- 



FlG. 10. — Right hand of Ostrich.^', radial carpal ossicle ; C^, ulnar carpal 

 ossicle; </», proximal phalanx of the index digit which has three pha- 

 langes ; di, phalanx or third digit ; /, ulna; iifl and nii, metacarpals of 

 second and third digits anchylosed together and with that of the poUex ; 

 p, proximal phalanx of pollex ; r, radius. 



faces for the three or four toes. The study of the very 

 young bird, however, has shown us that though no 

 tarsus can be distinguished in the adult, yet such a 



part does exist for a certaiji brief period of the bird' s- 

 life and then disappears. 



In its fate we have an interesting resemblance to the 

 condition which we have already found existing in the 

 crocodile, and which condition the bird exaggerates. 

 The upper part of the tarsus becomes not merely firmly 

 fixed to, but indistinguishably united with, the leg-bone, 

 or tibia, while the lower part of the tarsus becomes as 

 indistinguishably united with the coalesced metatarsals^ 

 and thus it comes about that no tarsus whatever is dis- 

 tinguishable in the adult. The apparent leg-bone (tibia) 

 is leg-bone with part of the tarsus also; the apparent 

 metatarsal bone is made up of metatarsal bones with the 

 other part of the tarsus also. The movement of the foot 

 on the leg takes place in the bird (as in the crocodile), 

 not between the leg and ankle, but in the middle of the 

 ankle itself. 



In the skeleton of the bird's fore-limb, or wing, the 

 hand is strangely different in aspect from the foot. There 

 is hardly any carpus (or wrist) visible. The metacarpus 

 is represented by a single complex bone formed of three 

 metacarpals anchylosed together, and there are only 

 three fingers, which are all more or less rudimentary. 



Here serial symmetry is more disguised than ever in 

 the bat, the difference between a bird's wing and a bird's 



Fig. 13. — Skeleton of a Plesiosaurus. 



leg being so great. And yet even here we meet with a 

 curious example of the tendency to vary similarly which 

 exists in serially homologous parts ; for in the bird' s 

 carpus there is a similar arrangement, though less 

 thoroughly carried out, to that which exists in the bird's 

 tarsus. The distal part of the carpus coalesces altogether 



with the metacarpus (as the distal part of the tarsus does 

 with the metacarpus), but the proximal part remains 

 distinct in the form of two separate carpal bones. 

 (7'(? be continued) 



St. George Mivart 



THE OBSERVATORY OF PARIS 



A RRANGEMENTS for the future management of the 

 -^~*- Observatoryat Paris are now complete. Contre-Amiral 

 (until recently Captain) Mouchez is appointed director, 

 with M. Maurice Loewy as sub-director — these appoint- 

 ments taking effect for five years. 



M. Mouchez was born at Madrid in 1821, but is the 

 son of French parents. He joined the Naval School at 

 Brest in 1837, and in 1839 commenced his nautical career 

 in the Fortune, which was taking part in the blockade of 

 Buenos Ayres. In 1840 he was appointed to the Favorite, 

 which proceeded on a circumnavigating expedition ex- 

 tending over five years. Having shown an early aptitude 

 for astronomical observations, he was intrusted with 

 them. On this voyage he became aware of the imperfect 

 determination of the latitudes and longitudes of some of 

 the sea-ports visited, and his attention was directed to 

 the construction of portable instruments for improving 

 them. In 1850 he embarked on board the Capricieuse, 

 also destined for a scientific voyage round the world, 

 which, like that of the Favorite, occupied five years. He 

 was charged by the Ddpot de la Marine with the survey 

 of the Rio de la Plata and the Brazils, a survey which 

 extended over about 3,000 miles. 



In i860 M. Mouchez was commissioned by the French 

 Government to visit England, for the purpose of reporting 

 upon the system of weather predictions organised by the 

 late Admiral Fitzroy, Leverrier at the time contemplating 

 the establishment in France of his own system of storm- 

 warnings. M. Mouchez, who was enthusiastic in favour 



of the Fitzroy arrangements, suggested that the D^piche 

 anglaise should be posted in the French ports, and 

 recommended a special meteorological organisation inde- 

 pendent of the Observatory at Paris. The proposition, 

 which was carried into effect, is said to have created 

 differences between Leverrier and the Minister of Marine. 

 M. Mouchez greatly interested himself from an early 

 period in his naval career in promoting astronomical and 

 physical studies amongst the officers of the Government 

 marine, and observations while at sea. His views are 

 noticed by Arago in his introductory work for scientific 

 travellers. 



In 1867 he commenced the survey of the coast of 

 Algeria, a work which, in consequence of repeated inter- 

 ruptions from his employment on other urgent missions, 

 was not completed until 1877. Thus in 1870, Contre- 

 Amiral Mouchez was sent with the French fleet to the 

 Baltic for the blockade of the Prussian coasts, but the 

 attempted blockade proving a failure, he was recalled and 

 charged with the defence of Havre, which place he 

 succeeded in preserving from a threatened hostile occu- 

 pation. 



In 1874 he was sent to the Island of St. Paul for the 

 observation of the transit of Venus, and next to that of 

 M. Janssen his mission may be considered the most 

 successful. At his suggestion the French Government 

 established, in 1875, an observatory at Montsouris, where 

 naval officers are practised in making astronomical obser- 

 vations, as also intending travellers, on the recommend- 

 ation of the Societe de Geographie. He is a member of 

 the Academy of Sciences in the section of Astronomy, 



