TRANSACTIONS OF SECTION C. 657 



to tlie Paris Museum ; while the late Professor Mitzopoulos — uncle of the present 

 distinguished Hector of the University of Athens — made a valuable and extensive 

 collection for the Athens Museum, which seems to have remained unnoticed until 

 1883, when the late Professor Dames, of Berlin, studied it and wrote a brief 

 account of some unique specimens contained in it. By far the most important exca- 

 vations hitherto made at Pikermi, however, are those which were undertaken by 

 Professor Albert Gaudry, under the auspices of the Paris Academy of Sciences, 

 between 1855 and 1860. These researches made known nearly all the essential 

 facts concerning the extinct mammalian fauna entombed in the Pikermi formation, 

 and led to several brilliant generalisations first published in Professor Gaudry's 

 well-known work on the geology and fossils of Attica in 1863. During the last 

 forty years only insignificant diggings have been attempted, among them being those 

 of the late Professors Neumayr, of Vienna, and Dames, of Berlin. 



Owing to the permanent mark left by former excavations it was easy to choose 

 sites for the new explorations of the British Museum. Three pits dug in continua- 

 tion of former workings soon yielded bones, and eventually furnished a very 

 extensive collection. Two trial pits at other points and in slightly diflerent 

 horizons produced nothing except two decayed bone-fragments. Water still 

 occurs even in dry weather a little beneath the bed of the stream ; but the 

 difficulties from this source are now much less than formerly owing to Mr. Skouses' 

 system of irrigation, by which the flowing stream of the ravine is usually diverted 

 at a point high up in its course. 



The Pikermi formation has already been well described by Professor Gaudry. 

 It consists chiefly of red marl, varied with lenticidar masses of rounded pebbles and 

 occasional yellowish sandy layers. Some of the pebble-beds are cemented into 

 hard conglomerate. The materials are such as might have been derived from the 

 mountain mass of Pentelicon, which forms the neighbouring high ground, the 

 marl itself being apparently the detritus of marble or other calcareous rock. The 

 formation is of great extent in Attica, and has only attracted special notice at 

 Pikermi because a stream happens to have cut a deep ravine through it and 

 exposed fine sections of the beds. 



As already observed by Professor Gaudry, the bones at Pikermi occur in two 

 definite horizons, those in the lower bed being less fragile and better preserved 

 than those in the upper bed. In two of our new pits, where the upper horizon is 

 well exposed, it is subdivided into two distinct layers by a nearly barren deposit of 

 marl from 30 to 45 cm. in thickness. The rotten nature of the bones is partly due 

 to their having been close to or at the surface and eroded by the present stream 

 before being covered by the three or four metres of superficial gravel which now 

 preserves them. The bones are also broken by the penetrating rootlets of trees. 

 The lower horizon is at a depth varying from one to two metres below the upper 

 horizon, and thus secure from destruction by surface agencies. Like each of the 

 two upper bone beds, it is rarely more than 30 cm. in thickness ; while the marl 

 above and below it is almost destitute of bones, rarely yielding more than rotten 

 fragments, but quite prolific in scattered land and fresh-water shells. The deepest 

 excavations beneath the lower bone-bed descended for about three and a half 

 metres and furnished the bone-fragments and shells throughout. 



So far as can be judged at present from the new excavations, the three bone- 

 beds of Pikermi are all of the same nature and contain the same mammalian 

 remains. The bones are massed together in inextricable confusion, and are often 

 mixed with a few pebbles. Large and small bones, whole specimens and splintered 

 fragments, all occur together ; but the small bones are usually most numerous at 

 the bottom of the layer. Several specimens of approximately the same shape 

 and size are often met with in groups, as if they had been sorted by water in 

 motion. On one occasion, for example, the scattered remains of many gazelles 

 were found together; in another spot there were several skulls of Tragoceras 

 in _ one _ mass ; in other cases nearly all the bones belonged to limbs of 

 Hipparion ; while one area was specially characterised by pieces of vertebral 

 column of ruminants and Hipparion, The elongated bones and elongated groups, 

 however, were never observed to trend in one definite direction, but were alwavs 



