Jan. 29, 1880] 



NATURE 



309 



by Cuvier still remains the most perfect yet discovered there. 

 This was the specimen said to have been given up to the 

 French army on the capture of Maestricht, and which is 

 now in the Paris Museum. So much was thought about it that 

 the story goes that the French gunners had orders not to point 

 their artillery to that portion of the town where it was known 

 to be. In America Prof. O. C. Marsh tells us, the group attained 

 a marvellous development, and was represented by very many 

 genera and species belonging to even diverse families In a 

 paper in the current number (January) of the American jfournal 

 of Science he gives some new characters of the group, based on 

 the examination of an enormous collection in the museum of 

 Yale College, which is calculated to contain the remains of not 

 less than 1,400 distinct individuals. In not a few of these the 

 skeleton is nearly if not quite complete, so that every part of its 

 structure can be determined with almost absolute certainty. 

 Already from this immense storehouse has Prof. Marsh made out 

 various important details of the anatomy of the group. In the 

 present paper he communicates several others which had escaped 

 other observers. Several specimens, one of which is figured, 

 prove the presence of a sternum which is of the true lacertilian 

 type. The entire pectoral arch and paddles in several genera 

 are described ; the general structure of the paddles is Cetacean 

 in type ; hyoid bones have been found. In some genera the 

 orbit was protected by a ring of osseous plates, composed of but 

 a single row- of plates overlapping; the transversa bone of 

 Cuvier (ecteopterygoid, Owen) is present in several of the genera. 

 The accuracy of Cuvicr's determination of the pterygoid bones 

 can no longer be called in question ; Cope errs in calling them 

 palatines. All these newly-discovered characters and facts indi- 

 cate a true lacertilian alliance, and a new sub-order of lizards 

 should be formed, to be called Mosasauria. 



New England Isopods. — In the Proceedings of the United 

 State;; National Museum (November 5, 1879) Oscar Harger 

 briefly describes the marine isopods collected by the United 

 States Commission of Fish and Fisheries. Fuller descriptions 

 with figures of most of the species are promised later. As new- 

 species are described J.mira sfinosa, from Banquereau, and Lep- 

 tochcha rapax, from Aunisquam. There are forty-three species 

 enumerated, of which eleven are to be found on the coasts of 

 Europe. 



THB Fossil Horses of Constantine.— Veterinary Surgeon 

 P. 11. Thomas has quite recently published an interesting 

 account of the remains of some fossil horses found in the neigh- 

 bourhood of Constantine, in Algeria. It will be remembered 

 that the environs of Constantine are traversed by large and deep 

 valleys, on the flanks of which, as far as an elevation -eldom 

 exceeding 600 metres, the stripes of a fluvial-lacustrine pliocene 

 formation lie stratified. These, at their base, are characterised by 

 the presence of a chalky marl, and towards their summits by 

 gritty conglomerates, pudding stones, and sand ; the fluvial lacus- 

 trine deposits contain a somewhat transition fauna-composed of 

 some 01 the larger vertebrates, amongst which two species of 

 horse have been found, one an Hipi arion and one very near to, if 

 not identical with, the Equus ttenonu (laudry), of the pliocene 

 of Europe. In the bottom of these valleys, at the base of the 

 steep banks of the larger rivers, turfy deposits are found, apper- 

 taining in all probability to a recent quaternary period in which 

 a fauna appear» — which, though showing some affinities to the 

 previously-mentioned fauna, is more clearly connected with that 

 actually existing. litre are to be found remains of a horse (Equus 

 caballus) differing by only a few secondary characters from the 

 actually living African horse ; an ass of small dimensions, 

 presenting in its dentition some characters calling to mind the 

 genus Hipparion, which genus had, however, disappeared since 

 the preceding geological period. In the grey marl which imme- 

 diately lie over the alluvial turf, and which appear to be very 

 recent, there will be found in the lowest strata the remains of 

 horses, himcd cattle, and molluscs, differing in no way from 

 those of the present day. In a middle stratum remains of flint 

 weapons have been found (at about 2 50 m. from the surface of 

 the soil), while at about 1 metre below this surface, vestiges of 

 the Roman occupation will be met with. 



PHYSICAL NOTES 

 Measurements of the movements of glaciers have hitherto 

 I termination of the yearly 



or daily mean velocity, or to showing that the motion of glaciers 



resembles that of liquids. Some new measurements by Herr 

 Koch and Fr. Klocke (Wied. Ann., No. 12) have been limited 

 to ascertaining the motion of a point of the surface in a vertical 

 plane parallel to the direction of length of the glacier, with a 

 view to finding the real nature of the glacier's progress, whether 

 continuous and in the same direction or not. Two scales were 

 placed, one vertical, the other horizontal, being attached to a 

 post, fixed half a metre deep in the ice, and having a cone of ice 

 and debris formed round it. This was on the west side of the 

 Morteratsch glacier, about ih km. from its principal extremity. 

 The observations were made in August and September, the 

 scales being watched by day only, through a fixed telescope with 

 cross-wires. The number of scale parts parsing the cross gave 

 the direct and horizontal components of the motion. Another 

 similar post with scales was set up near, and in the field of 

 vision. The observations proved that the motion of the glacier 

 is by no means uniform, for one and the >ame point may move 

 now upwards, now downwards, towards the mountain, or towards 

 the valley. Further, two points of the surface, about 50 to 

 60 metres separate from each other, may, at the same time, move 

 in different, and even in opposite directions. 



THE behaviour of membranes in sounding columns of air has 

 been recently investigated by Herr Kohlrausch (Wied. Ann., 

 No. 12), and with the following results (which sufficiently indi- 

 cate the line of research) : — I. Open membranes (freely in c in- 

 tact with the air on both sides) vibrate in the ventral segments 

 of stationary waves, and come to rest in the nodes ; covered 

 membranes (shut off from the external air on one side) vibrate 

 in the nodes and come to rest in the ventral segments. 2. A 

 fine open membrane stretched over a ring is a very sensitive 

 means of determining the position of the nodes in stationary 

 waves. 3. If a solid body be brought between two nodes of 

 the stationary vibrations of a pipe, the half-wave between these 

 two nodes contracts, while ihe others are lengthened, and the 

 pipe gives a tone corresponding to the longer half-waves, conse- 

 quently a deeper one. 



From a comparison of the temperature co-efficients of fluidity 

 and galvanic conductivity for a number of substances (Wied. 

 Ann., No. 12), Herr Grotriau find- that with increasing concen- 

 tration of a solution, both coefficients vary in the same sense. 

 In solutions of NH 4 C1, KC1, KBr, and KI, the galvanic con- 

 ductivity increases nearly in proportion to the percentage pro- 

 portion. The fluidity, on the other hand, varies but little with 

 the concentration. 



A slight improvement has been introduced into the Bunsen 

 grease-spot photometer by Herr Toepler (Wied. Ann., No. 12), 

 rendering the observati 111s much less dependent on the position 

 of the observer (the angle between his line of sight and the paper 

 screen). The . rease spot is done away with, and the thickness 

 of paper is reduced instead, to give a spot. Between two 

 very thin moderately transparent sheets of parchment paper, 

 having a small circular aperture, is placed a sheet of ordinary 

 strong paper. 



Dr. BaumgARTNER has recently made, in Prof. Pfaundler's 

 laboratory (Wied. Ann., No. 12), a series of determinations of 

 the specific heat of water by a method of mixtures, in which 

 boiling water was poured directly into the cold water of the calori- 

 meter. The specific heat at lco° (that at 0° = 1) was found i'O307 

 (as against 1-0130 by Kegnault ; P0220 Renault, according to 

 Bosscha's calculations, I 0302 v. Miinchhausen and VVUUner, 

 1*0720 Heinrichsen, i'i22oJamin and Amaury, I"I255 Marie 

 Stamo). 



The telephone has been found by Herr Niembller (Wied. 

 Ann.) capable of determining very quickly and accurately the 

 resistance of liquids. It is substituted for the galvanometer in a 

 galvanic bridge, and an induction current is us.ed ; then, if the 

 resistances compared are a large liquid resistance on the one 

 hand, and a Sieuiens's resistance-box on the other, so that the 

 electro-dynamic constants of the branches are very small; 

 if, further, a German-silver or platinum wire be used as 

 measuring wire, it is found that in the position where the 

 galvanometer shows no deflection, the tone in the telephone 

 has a well-marked minimum of intensity. Supposing the liquid 

 resistance has 2,000 units, a variation of it, even four units, 

 reveals itself in a displacement of the minimum position. 



For study of liquid waves Signor Bazzi lately used (N. Cim. 

 (3) 6, p. 98) a trough 6 m. long, 10 ctm. deep, and 5 ctm. w ide. 

 In one end of it dipped a wooden parallelepiped, which could 



