964 JOURNAL, BOMBAY NATURAL HIST. SOCIETY, Vol. XXV Hi. 
either side a row of stout bristles, with a pair of chitiuous hooks on 
the first abdominal segment, shield them from injury when the in- 
sect is creeping through the hairs of its host. Some have also a row 
of stout bristles or spines arranged across the ventral surface of the 
abdomen which reminds one forcibly of the abdominal ctenidium 
in the Nycteribiids and which probably serves a similar purpose. 
In the genus Strebla, Wiod, from which the family is named there 
are at least four peculiarities which have been developed as para- 
sitic adjuncts. First, there is a collar of many chitiuous spines beneath 
the head which seems to be analogous with the ctenidium of Nycteri- 
biids ; secondly, there is a collar with a few similar spines on the 
dorsal surface at the back of the head ; thirdly, on the surface of the 
head and directed forwards, there is a semi-circular plate with seven 
rows of spines below and two large ones above all directed backwards 
so as to facilitate progress forwards ; fourthly, there are two grooves 
along the sides of the thorax -which enable the very long pair of front 
legs to be tucked away when the parasite requires to protect them. 
The grooves are fringed along the margin with spines and are 
shaped to contain the tibial joint when the legs are folded. The 
front pair of legs are placed far in front of the middle and hind pair 
and are separated from them by nearly the whole length of the thorax. 
These extremely strange peculiarities in the insects’ morphology 
are difficult to make intelligible to the reader by a mere verbal de- 
scription. They are, however, clearly seen in the two well drawn and 
large plates at the end of Dr. Speiser’s paper which contains the best 
general account of the flies of this family that has yet been written.* 
Among certain Streblids of the genus Ascodipteron there is an 
extraordinary divergence between the male and female, both as regards 
appearance and life history. These insects are found in the Oriental 
region and may some day be obtained in India. The first member of 
this remarkable group was discovered in 1896 by Dr. Theodor Aden- 
samer of Vienna who found a solitary specimen embedded in the 
wing-membrane of a bat which he had brought back from Java.r 
Dissection of the internal organs under the microscope showed it 
to be a female Dipteron reduced by parasitism to a shapeless lump 
He rightly guessed that when the males were discovered they would 
prove to be free-living normal insects. We now know that the female 
is at first wdnged but imbeds herself in the bat, sheds her wings and 
legs and undergoes post-imaginal metamorphosis into a flask-shaped 
object. Her abdomen grows to such an extent that it surrounds and 
* “ Ueber die Strebliden, Fledermaus Parasiten aus der Gruppe der pupiparen 
Dipteren ” by P. Speiser (1900) Archiv fur Naturg. 66 Jahrg. Vol. I. p. 31. 2 Plates 
and Bibliography. 
t T. Adensanier : VheT Ascodipteron phyllorinae (n. gen. n. sp.) eine eigenthii- 
mliche Pupiparenforin ”. (1896). Sitzung.sb. K. Akad. der Wissenscliaft. Wien, 
Vol. 105. Pt. I. p.400. 2 Plates. 
