720 SUMMARY OF CURRENT RESEARCHES RELATING TO 



adult character (a plumose tarsal pul villus). Berlese's definition must 

 be retained, and the genus Trombidivm may be divided into two sub- 

 genera. Eutrombidium Verdun (= Allotrombidium Oudemans) and 

 Heterotrornbidium Yerdun (= Trombidium Oudemans). 



Oribatoidea of Illinois.* — Henry E. Ewing describes thirty-three 

 species, of which twelve are new. Diagnostic keys are given, and there 

 is a useful introduction to the study of this group of mites. 



Eastern Pacific Pycnogonids.t — Leon J. Cole reports on the 

 Pycnogonids taken by the 'Albatross' in 1904 in the Eastern Pacific. 

 The collection consisted of two specimens of Ascorhynchus agassizii 

 Schimkewitsch, which is very near A. glaber • an immature specimen of 

 Colossendeis gig as Hoek ; and three specimens of C. cucurbita sp. n., 

 which is closely allied to C. gigas, but has the proboscis with an upward 

 curve and the fourth joint of the palp longer than the second. 

 Attention is directed to the curious capsules which occur attached to 

 the legs of both sexes in Colossendeis. It is a singular fact that the 

 usual external egg-masses appear to be unknown in this genus, and 

 though Hoek discusses the possibility that the capsules may represent 

 egg-masses, he regards this as improbable. 



e. Crustacea. 



Regeneration of Antennae in Palaemon olfersi.t. — Oh. Oravier 

 describes a specimen of this fresh-water prawn which showed the 

 antennae in process of regeneration. 



Land Isopods of Lundy Island.§ — Bruce F. Cummings collected 

 11 species, 2 of which, Cylisticus convexus and Trichoniscus pygmseus, 

 have not yet been taken in the adjacent area of North Devon. A 

 handsome yellowish variety of Oniscus asellus is noted. 



Indian Barnacles. || — Nelson Annandale gives an account of the 

 Indian pedunculate Cirripedia in the family Lepadidae. He divides the 

 Pedunculata into Pollicipedidae, Iblidae, and Lepadidss, and the last into 

 four sub-families : — Oxynaspidinae, Lepadinae, Pcecilasmatiuaa, and 

 Alepadinae. He deals with convergence, variation, and distribution in 

 the Lepadidte, and gives a systematic account of the Indian species. 

 In discussing the cecology of Dichelaspis, he notes that there is no 

 evidence that even the internal hangers-on are detrimental to the crus- 

 taceans in whose gill-chamber they live. They may, perhaps, aid in 

 respiration, and in getting rid of small intruding organisms. The 

 weight of external epizoic forms must often be great. More than 600 

 specimens of D. grayi were attached to a single snake, and the number 

 of individuals of D. warwickii attached -to a single crab is often as 

 great. They may help to mask bottom-haunting crabs. In any case, 

 it is impossible to regard the species of Dichelaspis as actual parasites. 



* Bull. Illinois-State. Lab. Nat. Hist., vii. (1909) pp. 337-89 (3 pis. and 5 figs.). 



t Bull. Mus. Comp. Zool. Harvard, lii. (1909) pp. 185-92 (3 pis.). 



X Ann. Sci. Nat., ix. (1909) pp. 123-7 (2 figs.). 



§ Ann. Nat. Hist., iv. (1909) pp. 319-20. 



|| Mem. Indian Mus., ii. (1909) pp. 61-137 (3 pis.). 



