1916.| B.SunpDARA Raj: Freshwater Fish of Madras. Ay a 
water, especially when kept among moist water-plants. Like most 
other air-breathers it is never seen to perform the usual respiratory 
movements of fish. During the rains in Madras young Ophio- 
cephali are often caught on land in the course of their migrations : 
out of water they progress in a serpentine manner, by means of 
their pectoral fins and the alternate contractions of the lateral 
muscles of the body. During periods of drought they are known 
to bury themselves in the soft bottom mud of ponds.! 
All the species of Oftocephalus are monogamous and build 
nests? for depositing their eggs. Under favourable conditions 
O. striatus breeds twice a year, about January? and February and 
again in June and July; but the same pair do not seem to 
breed twice in the year. The nest consists of a circular clearing 
in grassy Swamps or in the weedy edges of ponds andrivers. Both 
parents, the malein particular, keep guard. The eggs, which are 
large (1°25 mm.) and float at the surface, are never numerous but 
vary from a few hundreds to a few thousands according to the 
size of the fish. Dr. A. Willey gives a full description of the nest, 
egg and young of this species in Spolta Zeylanica, Vol. VI, pp. 
108—123. The following is a brief résumé of facts observed 
by him. 
Eggs.—Translucent golden-yellow or amber-coloured. They 
are spread like a sheet, flush with the surface in a sub-circular area 
in the centre of the nest. Diameter of egg 1°25 mm. 
‘‘The floating eggs owe their buoyancy to the presence of a single large oil- 
globule which occupies the greater part of the ovum, and is immersed in the 
golden-yellow yolk. It is adjacent to the upper pole of the eg g, andin surface view 
under a low power of the microscope is seen to be surrounded by a narrow zone 
of the yolk, the whole being contained within a space bounded by the vitelline 
membrane.’ 
The subjoined table gives a summary of the chronological 
data ascertained by him regarding the external features of the 
development of O. striatus. 
Days after hatching. Total length. Principal events. 
I a 3755 mm. Yolk-sac circulation established ; 
pigment cells develop their black 
colouration; pigment begins to 
appear in eyes. 
2.and 3 475 to5 mm. Pectoral fins arise; mouth opens, 
and respiratory movements com- 
mence. 
4 Bi 0°75 mm, Larvze leaving the surface and swim - 
ming freely at all levels. Bright 
yellow spots over eyes. 
7 mm. Larvee swarming and_ turning in 
unison at the slightest concussion 
Caudal cartilages appear. 
™“s 

1 Day, Fishes of India, p. 303; Fauna of Brit. Ind., Il, p. 359. 
2 Col. Puckle (quoted by Day), Fishes of India, p. 362; Thomas, Rep. Prsc. 
S. Canara, p. 37 (1870). 
®* Thomas, Rep. Pisc. S. Canara, p. 74 ( pe er Freshwater Fish and 
Fishertes of India and Burma, p. 23 (eaten 187: 
