Covers SK 931–939 (9 sūtras), Aṣṭādhyāyī 1.2.65–73 in unbroken sequence: all present.
The ekaśeṣa ("one survives"): when several words in the same case are meant together (sahavivakṣā), one of them is retained and the rest drop, the survivor taking the number of the whole. The governing rule for words of like form, sarūpāṇām ekaśeṣa ekavibhaktau (SK 188, 1.2.64: vṛkṣaś ca vṛkṣaś ca → vṛkṣau), is not in this span — this prakaraṇa is the set of ekaśeṣas Pāṇini allows between words of unlike form, each rule naming which of the pair survives. Two threads run through the whole chapter: (i) the proviso of 931, tallakṣaṇaś ced eva viśeṣaḥ — the ekaśeṣa holds only if the entire difference between the words is the one the rule names (gotra/yuvan affix, gender, neuterness) — which SK carries forward into 932, 933, 935 and 937; and (ii) the closing observation under 939 that once the ekaśeṣa has operated there is no dvandva at all (no plurality of sup-ending words remains), so a surviving śirasī or panthānau takes neither compound accent, nor the prāṇyaṅga singular, nor a samāsānta. Two vārttika-clusters extend the section: on 938, which survivor among the pronouns themselves and which gender the surviving pronoun shows; on 939, the exclusion of single-hoofed animals. Ordering: SK order except that 934 (the brother/son pairs) is pulled down to sit with its fellow kinship rules 936–937, so that 933 and 935 — the two purely gender-made ekaśeṣas — stand together.
gārgyaś ca gārgyāyaṇaś ca → gārgyaugārgyau. Four counter-cases: gargagārgyāyaṇau (garga has no gotra affix: not vṛddha); gargagārgyau (no yuvan co-expressed); bhāgavittibhāgavittikau (bhāgavittika, ṭhak by 4.1.148, adds contempt and Sauvīra-hood — not tallakṣaṇa); gārgyavātsyāyanau (bases garga vs vatsa differ — not the entire difference; SK's text "gārgavātsyāyanau" read gārgya- with BM and TB). BM/TB: "vṛddha" rather than "gotra" signals that outside the apatya-adhikāra "gotra" means the everyday gotra — so no ekaśeṣa for aupagava (immediate son) + aupagavi (yuvan).gārgī ca gārgyāyaṇau ca → gargāḥ: gārgī (garga + yañ + ṅīp 4.1.16) survives, counts as masculine and plural, so the yañ takes luk by yañañoś ca (SK 1108, 2.4.64) with "astriyām" and "bahuṣu" carried in from 2.4.62 — hence gargāḥ, not gārgyaḥ. (The vigraha uses the dual gārgyāyaṇau on purpose: with only two persons there is no plural, no luk, and gārgyau would look the same in either gender, leaving puṃvat idle.) dākṣī ca dākṣāyaṇaś ca → dākṣī: dākṣī (dakṣa + iñ 4.1.95 + ṅīṣ 4.1.65) survives; on puṃvadbhāva the ṅīṣ withdraws and the result dākṣī is the masculine dual of dākṣi. The 931 proviso still binds: no ekaśeṣa in bhāgavittī ca bhāgavittikaś ca or gārgī ca vātsyāyanau ca.haṃsī ca haṃsaś ca → haṃsauhaṃsau; and precisely because the difference is gender-made, 1.2.64 (sarūpāṇām) cannot reach the pair. TB: "vṛddho yūnā" stops here, but "sarūpāṇām" carries on, so no ekaśeṣa in haṃsaś ca varaṭā ca (different forms, though gender is the only difference) nor in mātṛ "mother" + mātṛ "measurer" (mātārau / mātarau differ by the 6.4.11 lengthening). This rule is what 939 will override for herds.śuklaś ca śuklā ca śuklaṃ ca → śuklam (SK: tad idaṃ śuklam)śuklaḥ paṭaḥ, śuklā śāṭī, śuklaṃ vastram → tad idaṃ śuklam resolves into three ekaśeṣas, each keeping the neuter and taking the singular: sa ca sā ca tac ca → tat, ayaṃ ca iyaṃ ca idaṃ ca → idam, śuklaś ca śuklā ca śuklaṃ ca → śuklam (śukla follows its substantive's gender; paṭa etc. shown only to bring that out). Without the singular option: tānīmāni śuklāni. "anapuṃsakena" keeps śuklaṃ ca śuklaṃ ca → śukle (1.2.64, no singular treatment). BM: ekavat is what shows the ekaśeṣa section never works in the samāhāra sense — hence no odanam for odanaś ca odanaṃ ca.bhrātā ca svasā ca → bhrātarau; mātā ca pitā ca → pitarau / mātāpitaraubhrātā ca svasā ca → bhrātarau; putraś ca duhitā ca → putrau. Obligatory (no vā). Pulled here from its SK slot between 933 and 935.mātā ca pitā ca → pitarau; in the alternative the dvandva mātāpitarau (mātṛ first as the more venerable, ānaṅ by 6.3.25 = SK 921). TB's defence of 936–937 against the charge of redundancy: they are begun to bar mātarau / śvaśrvau alone in the joint sense.śvaśrūś ca śvaśuraś ca → śvaśurau; or the dvandva śvaśrūśvaśurau (śvaśrū first, the mother-in-law being venerable). SK's text "śvaśvā" for śvaśrvā is a dropped r; BM on this rule is missing from the source (a misfiled 1.1.71 block sits in its place).sa ca devadattaś ca → tausa ca devadattaś ca → tau (devadatta drops; no taddevadattau). Vārttika 1 tyadādīnāṃ mithaḥ sahoktau yat paraṃ tac chiṣyate: among pronouns themselves the one later in the gaṇa survives (śabdapara-vipratiṣedha): sa ca yaś ca → yau (yad follows tad in the list); the Bhāṣya allows the earlier too ("para" also = the desired one): sa ca yaś ca → tau; the gaṇa is not cut at dvi here — Bhāṣya's ahaṃ ca bhavāṃś ca → āvām. Vārttika 2 tyadāditaḥ śeṣe puṃnapuṃsakato liṅgavacanāni: the surviving pronoun expresses gender (liṅga-vacana = gender-expressive, not "gender and number") according to the masculine or neuter word co-expressed: sā ca devadattaś ca → tau (tad kept, takes devadatta's masculine), tac ca devadattaś ca yajñadattā ca → tāni; masculine + neuter together → neuter, being read later in the vārttika's "puṃ-napuṃsaka": tac ca devadattaś ca → te. Vārttika 3 advandvatatpuruṣaviśeṣaṇānām (SK's "-viśeṣānām" read -viśeṣaṇānām with BM/TB): not for a pronoun that qualifies a dvandva or tatpuruṣa — there it simply follows its substantive's gender: kukkuṭamayūryāv ime (ayaṃ ca iyaṃ ca → feminine ime, the dvandva being feminine by paravalliṅga 2.4.26; the masculinity due by vārttika 2 — or by 933 — is barred); mayūrīkukkuṭāv imau (a variant reading, beside the point since that dvandva is masculine anyway); tac ca sā ca → ardhapippalyau te (tat = pippalyardham, neuter; sā = ardhapippalī, feminine by 2.2.2; 935 would keep the neuter, but the tatpuruṣa is feminine and so is its qualifier — the telling form is the plural ardhapippalyas tāḥ, since dual te is the same in both genders).gauś ca gauś ca … → gāva imāḥgāvaḥ either way, so the fruit shows in the accompanying pronoun, gāva imāḥ (feminine; vārttika 2 of 938 does not intervene, on the strength of the Bhāṣya's own gāva imāḥ — or, TB, imāḥ is itself a feminine ekaśeṣa within the same domain). Counter-cases, each falling back to 933's masculine: rurava ime (ruru, the black antelope, not domestic); brāhmaṇāḥ (brāhmaṇī + brāhmaṇāḥ — persons, not paśu; else brāhmaṇya imāḥ); etau gāvau (a cow and a bull, not a herd: saṃgha must mean many to have force, an ekaśeṣa being of more than one anyway; else ete); vatsā ime (calves, young; the 1915 editor prefers varkarā ime). Vārttika anekaśapheṣv iti vācyam: only among animals not single-hoofed — horses excluded, so aśvā ime (masculine). SK's closing note ("iha sarvatra"): the ekaśeṣa is antaraṅga and blocks the dvandva that would otherwise obtain (else it would have no scope); once it has operated there is no dvandva, for want of plural sup-ending words — so śirasī, śirāṃsi (śiras + śiras) get neither the final udātta of samāsasya 6.1.223 nor the prāṇyaṅga singular of 2.4.2 (SK 906), and panthānau, panthānaḥ get no samāsānta a of 5.4.74 (which still has scope in apanthānau, where 5.4.72 makes it optional, so 7.1.86 cannot be said to presuppose its absence). Thus ends the ekaśeṣa-prakaraṇa.