No 11552, Wednesday 18 Nov 2015, Incognito

ACROSS
7   This is what Aryabhata was probably paid for inventing this (4) ZERO [C&DD]
8   Horny animal, before dark, makes pre-nuptial celebration (4,5) STAG NIGHT {STAG} {NIGHT}
10 Add finishing touches to a North European language (6) POLISH [DD]
11 After half of an Italian PM's party, cry in a house (8) BUNGALOW {BUNGAbunga}{LOW}
12 Fix back tough fish (8) PILCHARD {PILC<=}{HARD}

14 This, in a restaurant, may be the person serving or the guest (6) WAITER [DD]
16 Mother takes bachelor to a South African city (7) MOMBASA {MOM}{BA}{SA}
18 Treasury, after loss of money, was relocated to the mouth of a river (7) ESTUARY TrEASURY*
21 A long distance between a pole and India for a trip (6) SAFARI {S}{A}{FAR}{I}
23 Checks policemen who dropped gold (8) INSPECTS INSPECTorS
25 Punch on the chin for defensive play in bridge (8) UPPERCUT [DD]
27 Setter's cross in Karnataka city (6) MYSORE {MY}{SORE}
29 Settle old scores as a result of herpes (4,5) COLD SORES*
30 Crosby's search engine (4) BING [DD]

DOWN
1   Indian chief given room after five went away and resettled (8) GERONIMO {GIvEN+ROOM}*
2   Antelope's hat? (4) TOPI [DD]
3   Street in Omaha’s rebuilt after gas leakage caused disease (6) ASTHMA {ST} in {oMAHA}*
4   Dance. Dance with a Greek character (7) LAMBADA {A+LAMBDA}*

5   X, Y or other unidentified things (8) UNKNOWNS [CD]
6   Hag has hidden a Hindi actor (4) AGHA [T]
9   Thomas carried the fifth letter for them (5) THOSE {THOS}{abcdE}
13 Snake has head support (5) COBRA {CO}{BRA}

15 After drop of temperature, unties packages and gets engaged (2,3) IN USE UNtIES*
17,20 Railway stations advise us to be wary of these porters (8,7) SUITCASE LIFTERS [DD]
19 Giving up the job and going to bed (8) RETIRING [DD]
22 Snake has chip for food (5) ASPIC {ASP}{IC}

24 Doctor has it on both sides — a snack (6) SAMOSA {SA}{MO}{SA} Where is our eye doctor?
26 Fishes found in discredited baskets (4) EELS crEELS
28 Cries after alumnus boards ship (4) SOBS {S{OB}S}

GRID