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his conclusions are the result of several experiments. I confess, however, that 

 I was soraewbat sceptical with regard to this unique exceptional phenomenon in 

 the vertebrata. Professor Owen, to whom I wrote to ask whether -.he bisexual 

 structure of the genus Scrraniis was accepted by naturalists, replied that he for 

 one was certain tl;at tlie conclusion was based on erroneous observation. 1 

 ■wrote to Mr. Couch, of Pnlperro, for s-pecimens of the smooth Serranus, which 

 is sometimes caught in the crab pots oS the Cornish coast. He did not succeed, 

 I am soriy to say, in obtaining for me more than a single specimen ; this, on a 

 very careful examination, I found to present nothing approaching a bisexual 

 character. On this subject, therefore, I suspend my opinion. 



But the study of the development of animals makes us acquainted with 

 other modes of reproduction besides that which results from the union of the 

 sexes. If we take nuii.bers of individuals alone into consideration we shall find 

 many thousand times more creatures to be born by non- sexual reproduction than 

 by sexual reproduction. True, for the most part we find that this non-sexual 

 mode obtains amongst animals of very low organisation, but there are some very 

 striking exceptions to the rule. I dare say many in this room are acquainted 

 with that small jelly-like thing common in weedy pools, known by the name of 

 hydra. This animal throughout the whole of the spring and summer months 

 produces thousands of offspring, but not one from an fgg. The body of the 

 parent at first shows a little swelling in the form of a papilla, budding out from 

 one or two poitions of it ; in time this bud grows tentacles like the parent to 

 which in all respects it becomes similar. Towards the end of autumn, however, 

 when the November days become cold, this budding process cease?, and the hydra 

 produces on two different parts of the body one or two round bodies containing 

 ova and the same number of oval ones containing spermatozoa. The ova, when 

 mature, are pushed through the body-wall, and, after having been impregnated, 

 are attached to some water-weed awaiting the warm weather of spring, when 

 they wiU develope into young hydra. Here, then, we have two modes of repro- 

 duction — the cne sexual, the other gemmipparous or asexual. It is not, 

 therefore, true to say with Harvey " omne vivum ex ovo " as the hydra produces 

 many young ones, not from an egj, but directly from the substance of the 

 parent's body by a process analogous to that of the budding of plants. This 

 leads one, naturally enough, to say a few words on what has been termed 

 Parthenogenesis, a word which implies that there exists amongst certain animals 

 a power to produce young without intercourse with the male sex. It was in 

 1745 that Bonnet proved the astonishing fact that insects of the genus Aphis 

 produced young ones when no male insect was present, and further that these 

 young ones are all females, and that they gave birth to a fertile progeny in their 

 turn and so on to eleven generations. At the end of autumn, however, male 

 insects appear, and eggs are laid by the females, w hich attach themselves to the 

 bark of trees or other substances. These eggs lie doimant through the winter, 

 but in the spring of the following year give birth to the productive virgins I 

 have been speaking of. Thus it would seem we have a combination of viviparous 



