578 SUMMARY OF CURRENT RESEARCHES RELATING TO 



are " differential equation-divisions." But there is reduction in number 

 and quantity, for the spermatid has 18 bivalent, quantitatively reduced 

 chromosomes, plus an accessory chromosome. 



Observations on Glossina palpalis.* — E. Boubaudhas studied speci- 

 mens of this fly kept individually in separate glass tubes (closed in with 

 muslin), and fed with blood every 48 hours. Like its relatives, the fly 

 is "larviparous." The first laying maybe looked for in about three 

 weeks : the others follow every nine or ten days. A young larva is 

 hatched out of the egg immediately after the larva which preceded it 

 in the uterus has attained its full-grown form. The larval life lasts 

 nine or ten days ; the females, probably, live on an average about three 

 months, and reproduce 8-10 times. 



The pupation (in dry places) is described. Abortion and intra- 

 uterine pupation are not infrequent. The average duration of the pupal 

 life is 33 clays, but it may be modified by external conditions. Heat is 

 very fatal. Indeed the pupae cannot accommodate themselves to a tem- 

 perature about 25° G. In this there is suggested a practicable way of 

 waging war against the bearer of the germs of sleeping sickness. 



Life-history of Thrypticus smaragdinus.t — H. Liibben has been 

 successful in working out the life-history of this rare Dolichopid fly. 

 The larvae were found in the root-stocks of the reed, Arundo phragmites. 

 and they pupate there. The pupae have a very remarkable head arma- 

 ture or boring apparatus, and the abdominal tracheal " horns " are much 

 longer than the prothoracic pair. Attention is called to the conver- 

 gence between the Thrypticus pupae and that of some Cecidomyids, e.g. 

 Lasioptera indusa, which have a similar head-armature. 



Luminosity of Tropical Lampyridae.ij: — 0. Steche notes that the 

 intermittent character of the light is not due to periodic covering of the 

 luminous organ, for he observed the phenomenon in absolutely motion- 

 less forms. After paralysis with spider-poison the normal luminosity 

 continues, which is against, the idea that the respiratory movement of 

 air in the tracheae is a decisive factor in the illumination. Some intra- 

 cellular oxidation-process is suggested. If the connection with head 

 and breast be broken, the luminosity stops, and as the importance of 

 respiratory movements and blood-circulation does not seem to be great. 

 judging from the spider-bite experiment, the author infers that the 

 influence of the central nervous system is of moment. Even after the 

 nerve connection is cut, chemical or mechanical stimulation of the cells 

 results in luminosity, but the light is weak, somewhat different from the 

 normal, and not discontinuous. 



Pink Katydids as Mutants.§ — W. M. Wheeler calls attention to 

 the sporadic occurrence of pink individuals among the usually leaf -green 

 katydids (Locustidae belonging to the sub-families Phaneropterinae and 

 Pseudophyllinae). They are well known in Amblycorypha, which have 



* Comptes Eendus, cxlvi. (1908) pp. 362-5. 



t Zool. Jahrb., xxvi. (1908) pp. 319-32 (1 pi. and 6 figs.). 



X Zool. Auzeig., xxxii. (1908) pp. 710-12. 



§ Amer. Nat., xli. (1907) pp. 773-80. 



