BIHANG TILL K. SV. VET.-AKAD. HANDL. BAND 24. AFD. IV. N:038. 11 
specimens of equal size, excepting only in the largest males 
of C. poecilopus, which usually have their ventrals very long, 
reaching to or beyond the vent. 
mm —— -222X:X-<2  qÖ—-—-—r—s—oOoo————— KÖ-Äv———!ä-  '- = 
OC. poecilopus. OC. gobio. 
| 45,2] 57,5) 76,1| 42,5| 57,9| 75,5 
Q | 43,4] 62,7) 76,1| 42,4/ 58 | 75,8 
| Length of the ventral fins in Z of the length | 5|17,2 17,7| 20,1] 17,2) 17,7| 18,1 
OK URSRD OLAS A LL le MREL Es ar ale ad A EAT BRAT 
19 | 17,9] 18,1] 17,7) 17,7| 17,9|Å7,9 
| Length of the body in millimetres (average”) | 
In other specimens of C. poecilopus the ventrals some- 
times reach the vent, sometimes not, the latter being the case 
even in specimens of large size. Examining 51 examples, I 
found 22 in which the ventrals did not reach the vent (11 
of the smallest specimens [6 &, 5 2]. 3 of the middle-sized 
[I 3, 2 P), and 8 of the largest [3 &s, 5 2). Even in a few 
of my specimens of C. gobio I found the ventrals reach the 
vent. There exists on the whole in this respect a difference 
between the two forms, which, however, seems usually not 
to depend on the different length of the fins, but may be 
due to the length of the belly (the distance between the in- 
sertion of the ventrals and the vent or the beginning of the 
anal fin), which is generally greater in C. gobio than in C. 
poecilopus. 
The difference in depth of the tail. 
According to HEcKEL the tail of C. gobio is deeper than 
that of C. poecilopus. JEITTELES is the only author beside 
HECKEL who mentions this character. He shows that in this 
respect great variety exists in C. gobio, and argues on this 
ground that this character is of no importance as a distinction 
between the species. 
OC. poecilopus. | C. gobio. 
7,5] 76,1||'4$ 
Q | 43,4 62,7| 76,1 
Depth of the tail in 2 of the length of the ja! 4,5| 4,9) 5,21 5,5) 6 
LOGI ARE Fr SA Re, FIN OR - ; Fi RN 
a E 4.7| 4,9| 4,9) 5,5| 5, 
1 For the number of specimens in each group see p. 20. 
Length of the body in millimetres (average) | 
