THE REGION OF THE SPINAL CORD 423 
existence in Pantopoda of a double set of glands of similar character, 
one set in the basal segments of the appendage, and the other in 
the adjacent part of the body. 
In scorpions also, Kowalewsky has shown that the remarkable 
lymphatic organ situated along the whole length of the nerve-cord in 
the abdominal region takes up carmine grains and bacilli; an organ 
which in Androctonus does not form one continuous gland, but a 
number of separate, apparently irregularly grouped, glandular bodies. 
In addition to this median lymphatic gland, Kowalewsky has 
discovered in the scorpion a pair of lateral glands, to which he gives 
the name of lymphoid glands, which communicate with the thoracic 
body-cavity (i.e. the pseudoccele), are phagocytic, and, according to 
him, give origin to leucocytes by the proliferation of their lining 
cells, thus, as he remarks, reminding us of the nephridial capsules 
of Clepsine. These glands are so closely related in position to the 
coxal glands on each side that he has often thought that the lumen 
of the gland communicated with that of the coxal gland; he, how- 
ever, has persuaded himself that there is no true communication 
between the two glands. Neither of these organs appears to be 
segmental, and until we know how they are developed it is not 
possible to say whether they represent fused segmental organs or not. 
The evidence, then, is very strong that in the Crustacea and 
Arachnida the original segmental excretory organs do not disappear, 
but remain as ductless glands, of the nature of lymphatic glands, 
which supply leucocytes to the system. 
Further, the evidence shows that the nephric organs, or parts of 
the ccelom in close connection with these organs, may be transformed 
into ductless glands, which do not necessarily contain free leucocytes 
as do lymph-glands, but yet are of such great importance as excretory 
organs that their removal profoundly modifies the condition of the 
animal. Such a gland is the so-called adrenal or suprarenal body, 
disease of which is a feature of Addison’s disease; a gland which 
forms and presumably passes into the blood a substance of remark- 
able power in causing contraction of blood-vessels, a substance which 
has lately been prepared in crystalline form by Jokichi Takamine, 
and called by him “ adrenalin”; a gland, therefore, of very distinctly 
peculiar properties, which cannot be regarded as rudimentary, but is 
of vital importance for the due maintenance of the healthy state. 
In the Elasmobranchs two separate glandular organs have been 
