Folia archeologica 34.

24 VIOLA 'Г. DOBOSI Flint (Silex and Kiesel) 88% (from 2431 pes 2139) Quartzite 12% (from 2431 pes 292) b) Working The chipping of the intact pebble

—as ground form

—may be executed in different directions: crosswise (hemilith), lengthwise (ortholith) or obliquely (plagiolith) or else in the form of a sector. The half-pebbles can be cut in different geometrical forms (a quarter of a pebble, smaller than a quarter-pebble, prism, pyramid) (Fig. 4). These "geometrically broken pebbles" are in our opinion in the majority of cases similar implement preforms or even implements, as the Upper Palaeolithic blades: they are typological groups determinable and characteristic as well. Their occurrence on the type list is motivated, their proportion may be characteristical for an industry as an attendant industry alongside with the "leading types". Their emergence in the Middle Palaeolithics proves that the same implements occurring in the Lower Palaeolithics are not representatives of a "Praepalaeolithic". In Tata these groups are of a bigger size than the silex implements and are closer to Szelim. c) Sizes In his monograph Vértes evaluated 1965 implements; the groups according to length in the Skoflek material and among the implements taken out from the chips are the followings: measure groups old material % total (old + new) % - 20 mm 6.3 136 5.7 20—30 mm 44.2 1006 42 30—40 mm 38.5 925 38.6 40—50 mm 8.4 246 10.3 50—60 mm | 58 2.4 60—70 mm 2.5 18 0.7 70—80 mm ) 7 0.3 2396 100 average measure: 31.52 mm proportion of length

—width pes (Vértes + new) % Group I (1 : 1—1 : 1,5) 1644 64.4 Group II (1 : 1.5—1 : 2) 691 27.0 Group III (1 : 2—1 : 3) 185 7.2 Group IV (1 : 3—1 : 4) 26 1.0 Group V (1 : 4—1 : 5) 8 0.3 d) Typology As to the material of most Hungarian sites, the type list of the French system cannot be fully applied to Tata either (Fig. 5). This difference is increased