228 SPECIAL HISTOLOGY. 



thinner and fluid. When examined microscopically it pre- 

 sents, besides the spermatozoa, a moderate quantity of a clear 

 fluid, which, on the addition of water, presents irregular- sized 

 whitish flocculi and fragments, and is undoubtedly derived prin- 

 cipally from the vesiculae seminales. This gelatinising sub- 

 stance, which Henle described as fibrin, and Lehmann regards 

 as an albuminate of soda, has been described by Vauquelin, 

 who analysed human emitted semen, together with the substance 

 of the spermatic filaments, as spermatin, of which he found 6g, 

 whilst besides it there were present 902 water, 3g earthy phos- 

 phates, and Ig soda. When semen is dried, innumerable crystals 

 of the triple phosphate of magnesia and ammonia are formed 

 among the undestroyed spermatozoa, which generally, owing pro- 

 bably to the considerable quantity of carbonate of lime contained 

 in them, are not easily destructible. They may be demonstrated 

 in seminal spots even after a long time, when they are moistened ; 

 resist putrefaction for a lengthened period in water and animal 

 fluids (Donne observed them even after three months, in putrid 

 urine), and retain their form unchanged even after incineration 

 (Valentin). Acetic acid has but little effect upon the sper- 

 matic filaments. Caustic potass and soda render them pale, 

 and dissolve them, after from 15 to 30 minutes. Nitric acid 

 (20g) at first produces scarcely any change, afterwards dis- 

 solving them. In sulphuric acid their outline becomes ex- 

 tremely faint and they swell up, but are not entirely dissolved, 

 as are, for instance, the epithelial cells of the seminal tubes. 

 They are not coloured yellow by nitric acid and potass, nor 

 red by sugar and sulphuric acid. Nitrate of potass in a solu- 

 tion containing 6 per cent, does not dissolve them. In the 

 pure semen the filaments exhibit no movements, or scarcely any, 

 when it is too much concentrated. Their movements are first 

 visible in the contents of the vesiculte seminales, and in ejacu- 

 lated semen, or when pure semen is diluted. The movement 

 of these bodies is effected solely by the alternate flexure and 

 extension, or serpentine motion of the filamentary portion, in 

 which way are produced such lively and various undulating, 

 rotatory, quivering changes of place, during which the head or 

 body always precedes, that these elements of the semen were 

 formerly regarded as animals. The duration of the movements 

 depends upon various circumstances. In the dead body they 

 are not un frequently perceptible even 12 — 24 hours after 



