THE THEORY OF TITTLEBATS. 835 



and manners of fishes, and especially of the marine species, is hut 

 sporadic and fragmentary ; opportunities for ohservation are rare on 

 the sea-hottom, while, as for aquariums, the life there is so strained 

 and unnatural that we learn for the most part little more from that 

 source than one would learn of the intricacies of human existence by 

 watching the interiors of prisons and of convents, But even among 

 the few fish at all intimately known to us at present, there are several 

 which deserve high commendation for their able and conscientious dis- 

 charge of their paternal duties. Certain cat-fish, for example, and 

 many other species, construct nests like good fathers, and guard the 

 spawn deposited in them by their unnatural spouses. One siluroid 

 bearing the suggestive classical name of Arius actually carries the 

 eggs about with him in his own mouth, and there devotedly hatches 

 them. There is a fish of the Sea of Galilee, locally supposed to be the 

 very kind from whose mouth St. Peter took the miraculous denarius 

 for the payment of the apostles' tribute, and this pious and well- 

 principled creature (even his scientific name is CJiromis sacra) holds 

 his eggs in the same fashion, and hatches them out in his capacious 

 pharynx. Among the pipe-fish and sea-horses, including the well- 

 known hippocampus of the Mediterranean and the Westminster Aqua- 

 rium, Nature has gone one step further in the direction of parental 

 supervision. These fish have a regular pouch like the kangaroo, in 

 which the excellent papa retains the young till they are of full age to 

 shift for themselves. 



Yet even here it is the fond father, not the gay and careless 

 mother, who wheels about the family perambulator : only two known 

 cases occur among fish where the mother takes any part at all in the 

 hatching or education of her own young. One is a cat-fish from Brit- 

 ish Guiana, whose under surface becomes soft and spongy after the 

 spawning-season. The mother, as soon as she has laid her eggs, presses 

 them hard into this spongy integument by lying on top of them. 

 There they stick, and she carries them about in the pits thus formed, 

 much as the familiar Surinam toad carries about her hatching ova and 

 tadpoles in the skin of her back. The other instance is that of a sin- 

 gular pipe-fish from the Indian Ocean, who forms a pouch for her 

 young by allowing her ventral fins to coalesce with the soft skin of 

 her under surface. These two examples of devoted maternity, how- 

 ever, scarcely suffice to absolve the mother-fish as a class from the 

 general charge of heartless desertion brought against them by modern 

 ichthyologists. 



It is worth while, perhaps, to note in passing (since a theory of 

 tittlebats is nothing if not exhaustive) that the eggs of stickleback 

 are larger in proportion to the size of the full-grown individual than 

 those of any other known fish. Why is this ? Simply because the 

 stickleback are good fathers, who take great care of their callow 

 young. (I don't know what callow means, as applied to a fish, but I 



