BOYCOTT : ON VITRINA MA JOB. 129 



mass reconstructed from transverse sections, Fig. 5 a transverse 

 (sliglitly oblique) section a little below tbe middle, and Fig. 6 a 

 similar section showing the projection of the spout into the lumen 

 of the oviduct. The loose investing glands covering the upper part 

 of the mass (shown on one side in Fig. 5) consists of large cells with 

 enorm us nuclei (if they really are nuclei), which stain deeply with 

 hsematoxylin ; their cytoplasm also suggests that their secretion 

 is calcareous. Where and how these external glands discharge their 

 product I have not been able to determine. The lumen of the 

 spout is, in fixed specimens, only about 0-01 mm., and the orifice 

 by which it finally opens into the oviduct is smaller still. The eggs 

 of major ^ are about 0-33 mm. in diameter, those of the North 

 American limpida ^ about 1 mm. It seems at first sight extraordinary 

 that so narrow a passage should be interposed on the course which 

 the eggs have to follow,' and I searched in vain for some alternative 

 route, until I reflected that no one dissecting the human genitalia 

 for the first time would from the structure think it possible that a 

 baby should get through the cervical canal of the uterus. The 

 muscular tissue which forms the spout is no doubt responsible 

 for contracting the lumen to such small dimensions, but such tissue 

 is capable also of great expansion. As Dr. Bowell suggests, the 

 whole arrangement appears to be well adapted for retaining each 

 egg until it has been coated by the internal glands. Hence the species 

 may be found to lay eggs singly at rather long intervals. As to this 

 I have no information ; Moquin-Tandon says only that there are 

 eight to fifteen eggs stuck together in small masses. 



This oviducal mass of major has in some ways a striking 

 resemblance to the x organ of pyrenaica (Fig. 1). This latter opens 

 into the oviduct, but the eggs do not pass through it. The walls 

 (Figs. 7 and 8) have very little muscle except at the lower end, 

 where there is a spout quite similar to that of major, with a narrow 

 opening to the oviduct. Most of the substance of the wall is made 

 up of glandular tissue similar to that of the loose investing glands 

 of major. The cavity is relatively much larger, and nothing more 

 definite than amorphous granular material has been found in it. 

 I have not seen anything in the x organ corresponding to the 

 internal gland of the mass in major. It is quite possible, however, 

 that it is the function of both organs to contribute to the coats of the 

 egg, in major as it passes through and in pyrenaica as it travels 

 along the oviduct past the opening. The thick walls of the penis 

 in both pyrenaica and major contain a considerable quantity of 

 calcareous (?) glandular tissue, in appearance identical with that in 

 the X organ and external glands respectively. 



Simroth and others ^ boldly solve the tangle of these various 



^ Moquin-Tandon, loc. cit., p. 51. 

 2 G. H. Clapp, Nautilus, xvii, 1903, p. 91. 



^ See Eckardt, loc. cit. ; Taylor, Monograph, iii, 1914, p. 453 ; Bowell, 

 Irish Naturalist, xxiii, 1914, p. 210. 



