158 SUMMARY OF CQKKENT RESEARCHES RELATING TO 



granules, represent in the strict sense multiple centrosomes of the ordi- 

 nary spherical form. 2. The formation of the rod-like centrosome is 

 an early establishment of the middle piece of the spermatozoon. 3. 

 The entire middle piece of the spermatozoon of Dytiscus is undoubtedly 

 a centrosome, as is also the case in the spermatozoon of Ascaris megalo- 

 cephala^ and probably in other cases. 



Mouth-parts of some Larval Beetles.* — Gr. H. Carpenter and 

 Mabel C. MacDowell have studied the mouth-parts of some larv^ 

 belonging to the families Dascillidse and Scarab^eidse. They have dealt 

 especially with the maxillulae — appendages characteristic of the most 

 primitive Insects — which they find distinctly present in larval Dascillidse 

 and in a vestigial state in Scarabseid larvae. The fact that in these 

 beetle larvae alone among metabolic insects have the maxillulae as yet 

 been detected, suggests that the Coleoptera must be, in many respects 

 at least, a primitive order of the Endopterygota. The persistence of 

 the maxillulse in these larvse tells us not only that the campodeiform 

 type is venerable in the history of insect transformation, but, further, 

 that in the hard-cuticled beetle-grub, with its likeness to a bristle-tail 

 or a wood-louse, we have at least some hint as to the phylogeny of the 

 higher orders of winged Insects as a whole. 



Frontal Eyes of Ants.t — C. JuHus Caesar finds that the oceUi of 

 ants function as important visual auxiliaries to the compound eyes. 

 The latter are adapted for keen sight at short distances ; the ocelli serve 

 for orientation in relation to greater distances. This is particularly 

 necessary in flight. Wlien flight is given up and there is an associated 

 restriction of the practically important range of vision, there is degenera- 

 tion of the ocelli. In many species this has led to a loss of these organs. 

 The author deals with the minute structure of the ocelli — their lens, 

 cornea-making layer, retina, and optic nerve, and also discusses the 

 development. 



Absorption and Secretion in Intestine of Insects. J — Albrecht 

 Strudel describes an absorptive and a secretory phase in the same 

 epithelial cells of the intestine. The absorptive stage has been referred 

 to as a resting stage. There are transitional stages between the two 

 physiological conditions, as is well seen in Garahus and the cockroach. 

 It is probable that the double function is general. 



It was found that the peritrophic membrane served mainly as a 

 protective sheath. In the cockroach it keeps solid particles from going 

 into the caeca, only fluid being allowed through. 



Phorid causing Myiasis in Man.§ — E. Brunetti gives a description 

 of AphiochsetaferriuiLiiea Brunetti, a Phorid which has been proved to 

 attack man, infesting the intestine, and able to complete its life-history 

 as a human internal parasite. 



* Quart. Journ. Micr. Sci.,lvii. (1912) pp. 373-96 (3 pis. and 5 figs.), 



t Zool. Jahrb., xxxv. (1913) pp. 161-242 (4 pis. and 29 figs.). 



X Zool. Jahrb., xxxiii. (1913) pp. 165-224 (3 pis. and 3 figs.). 



§ Records Indian Museum, vii. (1912) pp. 83-6. 



