clxxxvi Journal of the Asiatic Society of Bengal. [N.S., XIII, 



At first sight adaptive modifications in structure frequently mask 

 taxonomic features in tadpoles. A good instance of the kind is to be 

 found in the genus Megalophyrs of the family Polobatidae. Most of the 

 larvae of this genus as yet known have the peculiar mouth-float briefly 

 described above and also remarkably long and slender tails, but the tad- 

 pole of M. hesseltit, which lives in Burma and the Malay Region, is of a 

 much more normal type. One Burmo- Malayan species of Mi.rohyla (M. 

 annectens) of the family Engystomatidao, in which the mouth-disk is usu- 

 ally absent, has, on the other hand, a funnel-shaped mouth-float analo- 

 gous to that of tadpoles of the peculiar Megalophrys type, though differ- 

 ing m details of structure. 



It would thus seem that convergence often plays a more important 

 part in the superficial characters of Anurous larvae than genetic relation- 

 al^' • iu j ?° s8lbl , e fchat in some instances the convergence has taken 

 place ,n the adults rather than in the larvae and that species in which the 

 adults seem to be related actually resemble one another because of paral- 



O „ i Z ^T.T f ^ an ° n account of descent from a common ancestor. 

 K?? hand the resemblance between tadpoles of different ancestry 

 ar Sl2 h su P er 5 cial « nd one finds that adaptations at Or* sight simi- 

 n rh™ O^ P rodu ? ed in different lines of modification. For instance, 

 Jul SSL?, 1 ap6 Vu 3 ° f B y° in which the ,llou th has become a power 



ment of rh« ?**"*{■ ^ u mod,fi ? a «on consists mainly in a great enlarge- 

 African frot ifT * P * ^Z**™ the lar va of a species of Helopkryne,ln 



SproTuced bv th« m,1 . y C r tl8nathid ™> a superficially similar structure 

 is produced by the equal enlargement of both lips. 



vet aLSnabTtn y ^ a t& W 6 ver y like th «* of Helophryne but not 

 SSSoSn 7 r known Indian species or genus, occurs in the hill- 



woukTnot h«^w i U ? Sl * S , fr0m What we know of other tadpoles, we 

 reffonship eS 8 *° **• When * he adu,t ia discovered, that a real 



Notes on the Anatomy of a Double Monostrosity in the Chick. 



By J). R. Bhattacharya. 



geJr^longTheTr Zt^l SL^T^^t' intimatel y COnnected *T 

 There is a dist TZt «JTt 7 i T heTe ls ' however, only a single head. 



individual The hS; ver * ebral r column , limbs and limbgirdles, to each 

 two 3*1 cords hl ^\ re ^on oithe medulla Oblongata divides to form 

 as wS to be expect uT^ t two individuals do not meet together 



viduaTs coalesce Mafol. « <■ "** ° £ the ad J acent sides of the fcw ° ■■* 

 a ventral position %Zl Bt ? mum - wh ich thus takes a lateral, instead of 



formation,^ I oth tS L' TT' theref ore, is contributed to, in its 

 viduals coalesce and he Z T^^ The b ody-cavities of both the indi- 

 and their attached vlhl i\ 8P c 8C ? aituated between the two sterna 

 which are cS t to both 2£? S- 5° ! nternaI ° r « ans ' «*»**% th . 09e 

 There is only a Snl se 2 V h " d, , v, I ? ua s « lie in this J oint body-cavity, 

 individuals :i-The hlart l.m! 1 fo,1 ow.ng organs common to both the 

 from the gullet down tn ST" ™ e g r eater portion of the digestive canal 

 liver, snlefn ™5. to J he ™. lddle of the ileum, the trachea, bronchi, 



duals. 



cloaca and bursa Fabricii. 



kidney; 



Ktjnhi 



TT • iViutatl on Coccus 



fulvmana psidii (Maskell). _^ _ __ .__„ 



Saltatory variationq * 

 antennal segments Tn mJE^l bug " The *yp«eal green bug has seven 

 number has l>een redu Jh \ 1 Waa so when ifc first appeared but the 

 plant in Bangalore 1^,1 fu eXCept in specimens found on a single 



B ore. m Ceylon the number is seven. In Uganda there 



