34 REV. MOSES HARVEY ON 



in the hatchery, and only when they are able to swim vigorously are they liberated iu 

 the outside waters to commence the battle of life. 



A high temperature of the water will hasten the development of the embryo, and a 

 low temperature will retard it ; so that the process fromim pregnatiou to birth may vary 

 from ten to forty days iu duration, according to the couditiou of the water. 



There is no more amazing aud interesting sight than the growth of the embryo, day 

 after day, as viewed with the microscope through its crystalline envelope. Every organ 

 is seen shaping itself, as if by some mystic rhythm, till the heart begins to pulsate and 

 propel the blood to all parts of the body and build up the frame from the tiny speck of 

 protoplasm to the bulky, voracious ranger of the sea. We can view it as " it is made in 

 secret and curiously wrought in the lowest parts of the earth," its " substance yet being 

 imperfect." "What profound mysteries too lie behind all that the microscope can reveal 

 and all that the eye of science can penetrate ! The secret of life is as impenetrable as 

 ever. The mysterious jDOwer that directs the movements of those molecules which shape 

 the living creature aud determine its destiny, who can pretend to define or fathom ! " In 

 Thy book were all my members written, which day by day were fashioned when as yet 

 there was none of them." "Fearfully and wonderfully made," is true of every living 

 creature. 



In many points the ova of the lobster presents a marked contrast to those of the cod- 

 fish, and differ from them greatly in the mode of development. The cod ova, as we have 

 seen, are impregnated in the water after they are extruded from the fish ; the lobster ova 

 are fecundated within the female before being extruded. The pairing of lobsters takes 

 place after they have fully recovered from the process ofshelliug. During copulation the 

 spermatozoa of the male are deposited, by its sexual organ, within the oviduct of the 

 female, and there coming into contact with the ova fecundation is accomplished, and not 

 till then are the eggs extruded. They are not, however, thrown into the water like the 

 cod ova. They come from the oviduct covered with a glutinous substance which enables 

 them to adhere to the swimmerets or fibrils underneath the tail. When in the act of 

 spawning the lobster bends its tail forward, in order to catch the ova as they are extruded. 

 The peculiar form of the tail, with its movable swimmerets, is admirably adapted to this 

 purpose. This process of spawning is accomplished in the course of one day — furnishing 

 another point of contrast to the codfish, which occupies several weeks in spawning. 



The newly-spawned ova are of a uniform dark green colour, but become more and 

 more transparent as the period of hatching approaches. They are carried by the lobster, 

 attached to the swimmerets until they hatch, the motion keeping them clean aud promoting 

 their development. The period that is occupied from the extrusion of the egg till the 

 hatching takes place is nine months. During all this time the ova are carried under the 

 tail, aud protected from foes by the rapid motion of the mother if attacked. The powerful 

 tail of the lobster enables it to shoot backwards through the water with extraordinary 

 rapidity. Mr. Nielsen, when investigating the habits of the lobster, was able, on one 

 occasion, to measure the distance it could go by a single stroke of its tail, and found it to 

 be 25 feet, in less than a second. 



The non-transparent character of the lobster ova, for several months after being 

 extruded, renders it difficult or impossible to study the embryo in the living egg, during 

 its first stages of development. When the larvae break from the egg, all the organs are 



