. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. 494 SEMEN. at regular intervals, which give to the corpus- cle sometimes an angular appearance, as in Pisa. The length of the rays holds an in- verse ratio to the size of the cells, and is, in most cases, either equal to, or double, their diameter. The peculiar form of these seminal ele- ments naturally provokes the question, whe- ther they really represent the developed spermatozoa, or whether they are not per- haps mere phases of developement. The relation in which they stand to the simple spermatic cells suggests a co
. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. 494 SEMEN. at regular intervals, which give to the corpus- cle sometimes an angular appearance, as in Pisa. The length of the rays holds an in- verse ratio to the size of the cells, and is, in most cases, either equal to, or double, their diameter. The peculiar form of these seminal ele- ments naturally provokes the question, whe- ther they really represent the developed spermatozoa, or whether they are not per- haps mere phases of developement. The relation in which they stand to the simple spermatic cells suggests a conjecture of this kind ; and the more so as the rays at- tached to them already present the greatest similarity with the usual filiform sperma- tozoa. We regret to say, that we are not yet in a position to decide this question with perfect certainty. From various obser- vations, however, the latter assumption gains in probability. Kollikcr has observed (in Calappa) that the adhering nucleus is lost at a later period; further, that in Portunus corru- gatus, the cell membrane gradually gets very much contracted ; whilst, on the other hand, the rays considerably lengthen themselves. If we consider, in addition to this, that radiated cells are found in Ilia Nucleus, which (j%) Fig. 380. A cell with rays from Ilia Nucleus. (After Kolliker.~) possess extraordinarily long fibres on a very small body; that finally in Pagurus, as it seems, the rays perfectly sever themselves from the corpuscles; that, at all events, developed radiating cells, without rays, are often found in the latter, it must induce us to share Kollikcr s opinion, that the ra- diating cells, at this stage of their formation, are not yet perfected ; but that they are more likely to be instrumental in the developement of ordinary spermatozoa. Such spermatozoa, however (if we except the genus Mysis, which is certainly unjustly divided from the Decapoda), have not yet been proved to exist in any of the animals belon
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