370 LYMPHATICS AND NERVES OF THE SPLEEN, [sect. 169. 



that Fulirer recently described as developing capillaries, making 

 use of them in constructing certain strange hypotheses on the 

 formation of blood in the spleen, but into these we cannot further 

 enter here. 



The human spleen possesses, relatively, very few lymphatic 

 vessels. The superficial ones run sparsely between the two enve- 

 lopes ; they are, however, scarcely recognisable, except in perfectly 

 healthy spleens and in the neighbourhood of the hilus. The deep 

 lymphatics are likewise few in number and of small diameter; 

 they are met with in the hilus, from whence they proceed along 

 with the arteries, although they cannot be followed nearly so far 

 as the latter. Both systems of lymphatics meet at the hilus, pass 

 through some glands in this situation, and finally become united 

 into one trunk, which opens into the thoracic duct opposite the 

 eleventh or twelfth vertebra. In morbid spleens, there is gene- 

 rally not a trace of the superficial lymphatics to be seen. 



The nerves of the spleen, consisting of numerous fine and some 

 thick tubes, with a moderate number of ' fibres of Remak,' arise 

 from the splenic plexus around the splenic artery by two or three 

 trunks, and are continued upon the arteries into the interior of the 

 organ, either singly or in pairs, which occasionally anastomose. 

 In the sheep and ox, these splenic nerves are truly colossal, so 

 that, when taken together, they equal the empty and contracted 

 splenic arteries in thickness ; their great size, however, is only to 

 be attributed to the unusually large number of fibres of Remak. 

 In animals, the nerves, which are entirely destitute of ganglia, 

 may be followed by the knife for a considerable distance into the 

 spleen, further than in man ; and with the aid of the microscope, 

 I have frequently seen them, even upon the arteries which support 

 the Malpighian corpuscles. Of the termination of the nerves, I 

 can only affirm that they cross into the pulp and can be seen on the 

 penicilli. They ultimately become as fine as the finest capillaries, 

 and no longer contain dark-bordered tubes ; at last, according to 

 Eckers observations (I.e. p. 149, fig. 10), they appear to end in free 

 extremities after bifurcation. In the calf, the nerves, upon arteries 

 of one line in diameter, measure o , o24'" to 0'028'"; upon penicilli 

 arteriarum, 00048'" to o"0056'"; in the midst of the pulp, 0'003'" 

 to o - oo4'". In trunklets of o"Oi2'" to o - 028'" in diameter, I have 

 observed a single dark-bordered nerve-fibre, whilst all the rest con- 

 sisted of a striated nucleated tissue, and this tissue alone was present 

 in the finer fibrils. It is impossible to regard this as of the nature 

 of connective tissue; but it appears probable, rather, that this, as 



