236 SUMMARY OF CURRENT RESEARCHES RELATING TO 



cell-contents combined with that of the cells of the connective tissue . 

 "What Guuo called a vesicula seminalis is really a lobated gland 

 which forms a secretion cajiablc of dissolving muscles and other pro- 

 toplasmic portions of the spider's prey, food being always taken in a 

 liquid form. 



Structure and Affinities of Phytopus.* — J. P. McMurrich confirms 

 Landois' statements as to the adult nature of Phi/idpus and the exist- 

 ence of two pairs of almost aborted limbs in a<ldition to the two pairs 

 developed. In P.jii/ri Sch. a pair of small tubercles may be seen on 

 either side just anterior to the genital jilate. They are smaller in the 

 form observed than they are represented in Landois' figures ; but 

 nevertheless decidedly larger than the wart-like structures which 

 support the body seta5. Of their existence the author has no doubt, 

 but that they represent legs is not quite so clear, thougli, on a priori 

 grounds, they must be supposed to do so. The Plujtopti are, he con- 

 siders, much more closely allied to Demodex thau to any other forms. 



Acari inhabiting the Q,uill of Feathers.f — E. L. Trouessart has 

 met with Syringoplnlus bipectinatus in the quills of a very large num- 

 ber of birds, so that the genus may be considered to be wide-spread. 

 The genus Picobia, found in the subcutaneous cellular tissue of Picua 

 canus, forms a distinct though closely allied genus, and should have 

 the same habits. The two genera constitute a small group, degraded 

 by parasitism, of the subfamily Cheliferidce, and are characterized by 

 the elongated vermicular form of the body and the atrophy of the palpi. 



Sijringophilus occurs in the quills of the wing and tail feathers 

 and often in those of the wing coverts. In the infected feathers the 

 quill has lost its transparency ; instead of the regular cones formed by 

 the retreat of the pith, only an opaque and pulverulent substance is 

 distinguishable, which under the Microscope is seen to be formed of 

 living but almost inert SyringophiU of all ages, surrounded by their 

 cast skins, blackish fceces, and the debris of the cones on which they 

 have fed. It is probable that they escape in the autumn, when the 

 dried-up feathers are ready to fall, and go in search of quarters in 

 new feathers, into which they enter by the still open upper umbilicus. 

 Their exit from the dried feathers is, on the contrary, made through the 

 lower umbilicus which becomes free at the autumnal moulting ; and 

 it is through this orifice likewise that Picrobia penetrate into the sub- 

 cutaneous cellular tissue. Confirmation is lent to this by the facts 

 observed in connection with the plumicolous Sarcoptidae. In winter 

 they retreat to the skin which is then covered by a thick down, and 

 like Pterolichus (Falciger) rostratus, j)enetrate the subcutaneous cellu- 

 lar tissue, but always by way of the quill of the feather, which is 

 thus only a passage and not the normal habitat as it is for Syringo- 

 philus. 



Presence of a Coxal Gland in Galeodes.+ — J. Macleod reports 

 the discovery of a coxal gland in the cephalothorax of Galeodes 



* Johns-Hopkins Univ. Circulars, iv. (1S84) p. 17. 

 t Comptes Kendus, xcix. (1884) pp. 1130-3. 

 t Bull. Acad. Belg., liii. (1884) pp. 655-6. 



