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In plants, likewise, a long and finely graduated series of transitions leads from bisexual to unisexual blossoms; and so in various other respects.
Summarizing this discussion we may conclude that in normal fertilization and in the inter-crossing of varieties all characters are paired, while in crosses between elementary species the differentiating marks are not mated. In order to distinguish these two great types of fertilization we will use the term bisexual for the one and unisexual for the other.
It must have struck most naturalists as a strange anomaly that, in the case of both animals and plants, species of the same family and even of the same genus, though agreeing closely with each other in almost their whole organisation, yet are not rarely, some of them hermaphrodites, and some of them unisexual.
When one sees the fragile woman aggressive, the masculinoid woman submissive, one may infer an education of experience that has brought the usually recessive glands into the foreground, and by their hyperactivity imposed a bisexuality of function upon a unisexual anatomic structure. A man apparently as formidable as a tyrannosaurus, may be ruled by his wife for the same reason.
But if, in fact, all hermaphrodites do occasionally intercross, the difference between them and unisexual species is, as far as function is concerned, very small.
It had a digestive tract long before it had a spinal cord; it had nerve ganglia long before it had a well-defined brain. It had sensation long before it had perception; it was unisexual long before it was bisexual; it had a shell long before it had a skeleton; it had instinct and reflex action long before it had self-consciousness and reason.
It must have struck most naturalists as a strange anomaly that, in the case of both animals and plants, species of the same family and even of the same genus, though agreeing closely with each other in almost their whole organisation, yet are not rarely, some of them hermaphrodites, and some of them unisexual.
In the family of the composites we find a group of genera with two forms of florets on each flower-head. The hermaphrodite ones are tubular with 5, or rarely 4, equal teeth, and occupy the center of the head. These are often called the flosculous florets or disk-florets. Those of the circumference are ligulate and ordinarily unisexual, without stamens.
But if, in fact, all hermaphrodites do occasionally intercross with other individuals, the difference between hermaphrodites and unisexual species, as far as function is concerned, becomes very small.
But if, in fact, all hermaphrodites do occasionally intercross with other individuals, the difference between hermaphrodites and unisexual species, as far as function is concerned, becomes very small.
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