XXI GLANDS ALIMENTARY SYSTEM 5 I 3 



the fourth joints or thighs of all the ambulatory legs, and these 

 glands without doubt act as cement-glands, emitting, like the 

 chelophoral glands of the larvae, a sticky thread or threads by 

 which the eggs and young are anchored to the ovigerous legs. 

 In some species of Nijmphon and of Colossendeis Hoek could 

 not find these, and he conjectures them to be conspicuous only 

 in the breeding season. While in most cases these glands open 

 by a single orifice or by a few pores grouped closely together, 

 in Barana, according to Dohrn, and especially in B. arenicola, 

 the pores are distributed over a wide area of the femoral joint.^ 

 In Discoarachne (Loman) and Trygaeus they open into a wide 

 chitinised sac with tubular orifice. While the function of these 

 last glands and of the larval glands seems plain enough, that of 

 those which occur in the palps and ovigerous legs of both sexes 

 remains doubtful. 



In their morphological nature the two groups of glands are 

 likewise in contrast, the former being unicellular glands, such as 

 occur in various parts of the integument of the body and limbs 

 of many Crustacea ; while the latter are segmentally arranged 

 and doubtless mesoblastic in origin, like the many other 

 segmental excretory organs (or coelomoducts) of various 

 Arthropods. 



By adding colouring matters (acid-fuchsin, etc.) to the water 

 in which the animals were living, Kowalevsky demonstrated 

 the presence of what he believed to be excretory organs in 

 Phoxichil'us, Ammothea, and Pallene. These are small groups of 

 cells, lying symmetrically near the posterior borders of the first 

 three body-segments, and also near the bases of the first joints of 

 the legs, dorsal to the alimentary canal.^ 



Alimentary System. — The proboscis is a very complicated 

 organ, and has been elaborately described by Dohrn.^ It is a 

 prolongation of the oral cavity, containing a highly developed 

 stomodaeum, but showing no sign of being built up of limbs or 



^ Ortmann, who would unite Barana with Ascorliy7ichus, observes : "Bei dieser 

 Gattung [Ascorhynchiis] konnte ich die Kittdriisen beobachten, die bei A. ramipes 

 niit dem von Barana castelnaudi [casteUi] Dohrn, bei A. cryiotojnjgius mit Barana 

 arenicola iibereinstimmen und also die primitivsten Formen der Ausbildung zeigen." 

 —Zool. Jahrb. Syst. v., 1891, p. 159. 



2 M6m. Acad. Sci. St-Petersb. (vii.), xxxviii., 1892. 



•■' Fauna u. Flora G. von Neapcl, iii. Monogr. 1881, p. 46 ; see also Loman, 

 J. C. C, Tijc/schr. D. Ned. Dierk. Vcr. (2), viii., 1907, p. 259. 



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