COITUS. 889 



mains to be said upon this subject after our discussion, in connection with the circulatory 

 system, of the general structure of erectile tissues. The cavernous and spou. 

 of the penis are usually taken as the type of erectile organs. In these parts, the art 

 are large, contorted, provided with unusually thick muscular coats, and connected with 

 the veins by vessels considerably larger than the true capillaries. They are supported 

 by a strong fibrous net-work of trabeculse which contains non-striated muscular fibres ; 

 so that, when the blood-vessels are completely filled, the organ becomes enlarged and 

 hardened and can penetrate the vagina. Researches upon the nerves of erection show con- 

 clusively that the vessels of erectile tissues are distended by an enlargement of the 

 arterioles of supply, and that there is not simply a stasis of blood produced by constric- 

 tion of the veins, except, perhaps, for a short time, during the period of most intense 

 venereal excitement. In experiments upon dogs, Eckhard discovered a nerve derived 

 from the sacral plexus, stimulation of which produced an increase in the flow of blood 

 through the penis, attended with all the phenomena of erection. This nerve arises by 

 two roots at the sacral plexus, from the first to the third sacral nerves. In the experi- 

 ments referred to, by a comparison of the quantity of venous blood coining from the 

 penis before and during the stimulation of the nerve, Eckhard found a great increase 

 during erection. It is probable that, in addition to the arterial dilatation, when the penis 

 attains its maximum of rigidity, there is a certain amount of obstruction to the outflow 

 of blood, by compression of the veins, and that the rigidity is increased by contraction 

 of the trabecular muscular fibres of the corpora cavernosa. 



During erection, the penis becomes exquisitely sensitive, especially at the glans ; and the 

 introduction of the organ into the vagina, pressure by the constrictor muscle, and friction, 

 increase this sensibility, until the venereal orgasm occurs. At this time, there is a pecul- 

 iar and indefinable sensation, almost immediately followed by spasmodic contractions of 

 the vesiculge seminales and the ejaculatory muscles, and, at the climax of the orgasm, the 

 semen is forcibly discharged from the urethra. This is followed by a feeling of lassitude, 

 a general sense of fatigue of the generative organs, flaccidity of the penis, and it is some 

 time before the venereal appetite can be again excited. Although this is the physiolo- 

 gical mechanism of a seminal discharge, friction of the- parts is not absolutely necessary, 

 as is shown by the occurrence of orgasm during sleep, which is liable to take place in 

 healthy men after prolonged continence. 



After the seminal fluid has been ejaculated during intercourse, the generative act, as 

 far as the male is concerned, is accomplished. It now remains for us to study the action 

 of the female and the process by which the spermatozoids are brought in contact with 

 the ovum. 



Action of the Female. If we can credit the statements made to physicians in their 

 professional intercourse and we have few other reliable sources of information there 

 are some females, in whom the generative function is performed, even to the extent <>t' 

 bearing children, who have no actual knowledge of a true venereal orpism: but there 

 are others who experience an orgasm fully as intense as that which accompanies ejacula- 

 tion in the male. There is, therefore, the important difference in the sexes, that prelimi- 

 nary excitement and an orgasm are necessary to the performance of the <,-vn.-rati\ . 

 in the male, but are not essential in the female. Still, there can bo <canvly a b.ubt but 

 that venereal excitement in the female facilitates conception, other conditions I . 

 favorable. 



The first intercourse in the female is usually more or loss painful, on nemiint of 

 ture of the hymen, and the external organs are unduly sensitive until tho parts are 

 healed. After this, if there bo a preliminary excitement there i> a certain u 

 erection of the clitoris (which corresponds to the penis) and of tho erectile bulb; 

 at the vaginal orifice. There is also an increase in the secretions about these parts ai 

 there may be an ejaculation from two glands opening near the labia mm..:- 



