380 REPORT OF THE COMMISSIONER OF FISHERIES. 
. shows that while in some species 2 ridges may be coalesced into 1, or 
an additional ridge may be interpolated, barring such fluctuations, 
which are occasionally found even on opposite sides in the same spe- 
cies, the homologue of any ridge is present in all members of the 
family. The ridges are most conspicuous in the large Amblyopsis, 
though really more highly developed in the smaller Zroglichthys and 
Typhlichthys. In the accompanying figures homologous ridges bear 
identical numbers. It will be seen from figures of Amblyopsis (1, 2, 
and 3, pl. 1), which may be taken as the type, that the ridges form 
transverse (ridges 1, 2, 3, 4, 6, 7, 9, 10, 12, 18, and other series) or 
horizontal (ridges 5, 7, 11) series. Over the lateral line canals of the 
head the ridges are usually at right angles to the canals. On the sides 
of the head the vertical ridges ferm more (Amblyopsis, fig. 1, pl. 1, 
and Chologaster, fig. 1, pl. 1) or less (Zyphlichthys, fig. 5, pl. 1, and 
especially Troglichthys, fig. 4, pl. 11) broken transverse lines. 
The papille in a number of the ridges were counted to ascertain 
whether or not the numbers were uniform in the same and in different 
species. The results of this count are given in the following table. 
The similarity is not marked, even in the two specimens of Amblyopsis. 
The numbers in the first column of the table correspond to the num- 
bers of the ridges of the figures. 
Number of papille in tactile ridges. 
lar | Typh- || : ‘| Typh- 
Amblyopsis spe- hesencne lichthys || Amblyopsis spe- caeeai lichthys 
Numbers leeus, liferus, |Stbterra-|/Numbers leeus. liferus, |Subterra- 
of ridges | | neus. | of ridges neous. 
shown | = ———_]] shown = | 
in cuts. Specimen|Specimen Specimen Specimen|| in cuts. Specimen Specimen Specimen Specimen 
86mm. | 108mm.) 51 mm. | 70 mm, 86mm. | 108 mm.} 51mm. | 70mm. 
| long. long. long. | long. long. long. long. long. 
| 
| | | 1] 
ie 21 22 (2?) | 19 24 21 | 
Dia| 13 18 8 | 15 | 25 11 
3 | 16 16 a 9 26 23 
4 15 23 8 14 27 18 
5 | 17 20 7 9 28 | 50 
6 | 12 20 6 11 5g it a aet 
ry a 14 ai19 a7 | a 10 o (als 
ul b12 b14 b9 b7 30 | 12 
onal 6 6 | 3 5 31 12 
| f @il ; 32 15 
9 lf 518 } 5 8 33 19 
10 8 13 4 Out. 34 | 23 
11 | 18 29 17 11 | { a 37 
ye 23 Wz | Out 12 95 bY 
13 16 20 ; Out 11 1 | e138 
14 11 18 13 a || 13 
G21 ne krteersss al.9 Ons | | a 30 
15 DEF 3 | Ree cee a2.8 b9 36 b5 
a | Chis Paseo mecee b6 ell | 22 | om) 
| (CD ae nee c4 d20 | a 10 
16 20 ie Nome: 30 ly 22 
17 21 250 Soe sear 14 ae 
18 19 18 Cal ern | 87 De 
19 27 essed | | 
| pa RO COGS 1) Oe pearacn SSS | 38 { : 10 
| 5 1) : aealal 
0 D4 BL | ea ae : 
3 39 | 9 
| i ‘ \ | 40 20 
| ae) ay 1 be If pl aes eal i 
| op | 21 | eee 20 || 42 14 | 
23 18) teen See | Sisal ee See 43 | 15 | 
